#At file:///mnt/sda7/work/mysql-next-mr-opt-backporting-wl4897/ based on revid:tor.didriksen@stripped
3358 Gleb Shchepa 2011-04-01
WL#4897: Add EXPLAIN INSERT/UPDATE/DELETE
WL#4897 implements EXPLAIN command for INSERT, REPLACE and
single- and multi-table UPDATE and DELETE queries.
@ mysql-test/include/explain_non_select.inc
Coverage and regresstion tests and sanity checks for WL#4897.
@ mysql-test/r/explain_non_select.result
Coverage and regresstion tests and sanity checks for WL#4897.
@ mysql-test/t/explain_non_select.test
Coverage and regresstion tests and sanity checks for WL#4897.
@ sql/CMakeLists.txt
New opt_explain.cc source file has been added.
@ sql/opt_explain.cc
WL#4897: Add EXPLAIN INSERT/UPDATE/DELETE
The select_describe() functions has been refactored into
msg_describe() and select_describe () global functions and
a few local auxiliary classes: Explain, Explain_msg,
Explain_table_base, Explain_union and Explain_join.
Also the functionality of select_describe() has been
improved to serve top-JOIN-less EXPLAIN queries (EXPLAIN
single-table UPDATE and DELETE) with the help of the new
global table_describe() function and auxiliary Explain_table
class.
explain_send class and explain_data_modification() function
have been added to adapt select_insert, multi_update and
multi_delete classes to work in EXPLAIN context (to
implement EXPLAIN INSERT...SELECT and EXPLAIN multi-table
UPDATE and DELETE commands).
@ sql/opt_explain.h
WL#4897: Add EXPLAIN INSERT/UPDATE/DELETE
Signatures of new msg_describe(), bool table_describe() and
explain_data_modification() functions have been added.
Modified declaration for the select_describe() function has
been moved there from the sql_select.cc file.
@ sql/opt_range.h
WL#4897: Add EXPLAIN INSERT/UPDATE/DELETE
Minor change: unnecessary friending of the select_describe()
function has been removed.
@ sql/sql_class.h
WL#4897: Add EXPLAIN INSERT/UPDATE/DELETE
The select_result::reset_offset_limit_cnt() method has been added
to reset protected offset_limit_cnt field.
@ sql/sql_delete.cc
WL#4897: Add EXPLAIN INSERT/UPDATE/DELETE
The mysql_delete() function has been improved to work in the
EXPLAIN multi-table DELETE context to produce EXPLAIN instead
table data modification.
@ sql/sql_insert.cc
WL#4897: Add EXPLAIN INSERT/UPDATE/DELETE
The mysql_insert() function has been improved to work in the
EXPLAIN INSERT...SELECT context to produce EXPLAIN instead
table data modification.
@ sql/sql_parse.cc
WL#4897: Add EXPLAIN INSERT/UPDATE/DELETE
INSERT...SELECT, REPLACE...SELECT and multi-table UPDATE/DELETE
handlers have been improved to work with EXPLAIN of these
queries.
@ sql/sql_select.cc
WL#4897: Add EXPLAIN INSERT/UPDATE/DELETE
The select_describe() function has been moved to opt_explain.{h,cc}
files and refactored.
@ sql/sql_show.cc
WL#4897: Add EXPLAIN INSERT/UPDATE/DELETE
Minor cleanup.
@ sql/sql_update.cc
WL#4897: Add EXPLAIN INSERT/UPDATE/DELETE
The mysql_delete() function has been improved to work in the
EXPLAIN multi-table UPDATE context to produce EXPLAIN instead
table data modification.
@ sql/sql_yacc.yy
WL#4897: Add EXPLAIN INSERT/UPDATE/DELETE
New EXPLAIN INSERT/REPLACE/UPDATE/DELETE syntax has been added.
added:
mysql-test/include/explain_non_select.inc
mysql-test/r/explain_non_select.result
mysql-test/t/explain_non_select.test
sql/opt_explain.cc
sql/opt_explain.h
modified:
sql/CMakeLists.txt
sql/opt_range.h
sql/sql_class.h
sql/sql_delete.cc
sql/sql_insert.cc
sql/sql_parse.cc
sql/sql_select.cc
sql/sql_show.cc
sql/sql_update.cc
sql/sql_yacc.yy
=== added file 'mysql-test/include/explain_non_select.inc'
--- a/mysql-test/include/explain_non_select.inc 1970-01-01 00:00:00 +0000
+++ b/mysql-test/include/explain_non_select.inc 2011-04-01 13:53:57 +0000
@@ -0,0 +1,63 @@
+--echo #
+--echo # query: $query
+--echo # select: $select
+--echo #
+
+if ($select) {
+--disable_query_log
+--eval $select INTO OUTFILE '$MYSQLTEST_VARDIR/tmp/before_explain.txt'
+--enable_query_log
+}
+
+--eval EXPLAIN $query
+if (`SELECT ROW_COUNT() > 0`) {
+--echo # Erroneous query: EXPLAIN $query
+--die Unexpected ROW_COUNT() <> 0
+}
+
+--eval EXPLAIN EXTENDED $query
+if (`SELECT ROW_COUNT() > 0`) {
+--echo # Erroneous query: EXPLAIN EXTENDED $query
+--die Unexpected ROW_COUNT() <> 0
+}
+
+if ($select) {
+--eval EXPLAIN EXTENDED $select
+}
+
+--disable_query_log
+
+if ($select) {
+--eval $select INTO OUTFILE '$MYSQLTEST_VARDIR/tmp/after_explain.txt'
+--diff_files '$MYSQLTEST_VARDIR/tmp/before_explain.txt' '$MYSQLTEST_VARDIR/tmp/after_explain.txt'
+--remove_file '$MYSQLTEST_VARDIR/tmp/before_explain.txt'
+--remove_file '$MYSQLTEST_VARDIR/tmp/after_explain.txt'
+}
+
+FLUSH STATUS;
+FLUSH TABLES;
+if ($select) {
+--disable_result_log
+--eval $select
+--enable_result_log
+--echo # Status of "equivalent" SELECT query execution:
+SHOW STATUS WHERE (Variable_name LIKE 'Sort%' OR
+ Variable_name LIKE 'Handler_read_%') AND Value <> 0;
+}
+
+FLUSH STATUS;
+FLUSH TABLES;
+--eval $query
+--echo # Status of testing query execution:
+SHOW STATUS WHERE (Variable_name LIKE 'Sort%' OR
+ Variable_name LIKE 'Handler_read_%' OR
+ Variable_name = 'Handler_write' OR
+ Variable_name = 'Handler_update' OR
+ Variable_name = 'Handler_delete') AND Value <> 0;
+
+--let $query=
+--let $select=
+
+--enable_query_log
+
+--echo
=== added file 'mysql-test/r/explain_non_select.result'
--- a/mysql-test/r/explain_non_select.result 1970-01-01 00:00:00 +0000
+++ b/mysql-test/r/explain_non_select.result 2011-04-01 13:53:57 +0000
@@ -0,0 +1,1816 @@
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+#
+# query: UPDATE t1 SET a = 10 WHERE a < 10
+# select: SELECT * FROM t1 WHERE a < 10
+#
+EXPLAIN UPDATE t1 SET a = 10 WHERE a < 10;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where
+EXPLAIN EXTENDED UPDATE t1 SET a = 10 WHERE a < 10;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a < 10;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`a` < 10)
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd_next 4
+Handler_update 3
+
+DROP TABLE t1;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+#
+# query: DELETE FROM t1 WHERE a < 10
+# select: SELECT * FROM t1 WHERE a < 10
+#
+EXPLAIN DELETE FROM t1 WHERE a < 10;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where
+EXPLAIN EXTENDED DELETE FROM t1 WHERE a < 10;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a < 10;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`a` < 10)
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 3
+Handler_read_rnd_next 4
+
+DROP TABLE t1;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+#
+# query: DELETE FROM t1 USING t1 WHERE a = 1
+# select: SELECT * FROM t1 WHERE a = 1
+#
+EXPLAIN DELETE FROM t1 USING t1 WHERE a = 1;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where
+EXPLAIN EXTENDED DELETE FROM t1 USING t1 WHERE a = 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a = 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`a` = 1)
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 1
+Handler_read_rnd_next 4
+
+DROP TABLE t1;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+#
+# query: UPDATE t1, t2 SET t1.a = 10 WHERE t1.a = 1
+# select: SELECT * FROM t1, t2 WHERE t1.a = 1
+#
+EXPLAIN UPDATE t1, t2 SET t1.a = 10 WHERE t1.a = 1;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where
+1 SIMPLE t2 ALL NULL NULL NULL NULL 3 Using join buffer (BNL, incremental buffers)
+EXPLAIN EXTENDED UPDATE t1, t2 SET t1.a = 10 WHERE t1.a = 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+1 SIMPLE t2 ALL NULL NULL NULL NULL 3 100.00 Using join buffer (BNL, incremental buffers)
+EXPLAIN EXTENDED SELECT * FROM t1, t2 WHERE t1.a = 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+1 SIMPLE t2 ALL NULL NULL NULL NULL 3 100.00 Using join buffer (BNL, incremental buffers)
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t1` join `test`.`t2` where (`test`.`t1`.`a` = 1)
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 8
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd_next 8
+Handler_update 1
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+#
+# query: UPDATE t1 t11, (SELECT * FROM t2) t12 SET t11.a = 10 WHERE t11.a = 1
+# select: SELECT * FROM t1 t11, (SELECT * FROM t2) t12 WHERE t11.a = 1
+#
+EXPLAIN UPDATE t1 t11, (SELECT * FROM t2) t12 SET t11.a = 10 WHERE t11.a = 1;
+id select_type table type possible_keys key key_len ref rows Extra
+1 PRIMARY t11 ALL NULL NULL NULL NULL 3 Using where
+1 PRIMARY <derived2> ALL NULL NULL NULL NULL 3 Using join buffer (BNL, incremental buffers)
+2 DERIVED t2 ALL NULL NULL NULL NULL 3
+EXPLAIN EXTENDED UPDATE t1 t11, (SELECT * FROM t2) t12 SET t11.a = 10 WHERE t11.a = 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t11 ALL NULL NULL NULL NULL 3 100.00 Using where
+1 PRIMARY <derived2> ALL NULL NULL NULL NULL 3 100.00 Using join buffer (BNL, incremental buffers)
+2 DERIVED t2 ALL NULL NULL NULL NULL 3 100.00
+EXPLAIN EXTENDED SELECT * FROM t1 t11, (SELECT * FROM t2) t12 WHERE t11.a = 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t11 ALL NULL NULL NULL NULL 3 100.00 Using where
+1 PRIMARY <derived2> ALL NULL NULL NULL NULL 3 100.00 Using join buffer (BNL, incremental buffers)
+2 DERIVED t2 ALL NULL NULL NULL NULL 3 100.00
+Warnings:
+Note 1003 select `test`.`t11`.`a` AS `a`,`t12`.`b` AS `b` from `test`.`t1` `t11` join (select `test`.`t2`.`b` AS `b` from `test`.`t2`) `t12` where (`test`.`t11`.`a` = 1)
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 12
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd_next 12
+Handler_update 1
+Handler_write 3
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+#
+# query: UPDATE t1 SET a = 10 WHERE 1 IN (SELECT 1 FROM t2 WHERE t2.b < 3)
+# select: SELECT * FROM t1 WHERE 1 IN (SELECT 1 FROM t2 WHERE t2.b < 3)
+#
+EXPLAIN UPDATE t1 SET a = 10 WHERE 1 IN (SELECT 1 FROM t2 WHERE t2.b < 3);
+id select_type table type possible_keys key key_len ref rows Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 3 Using where
+2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 3 Using where
+EXPLAIN EXTENDED UPDATE t1 SET a = 10 WHERE 1 IN (SELECT 1 FROM t2 WHERE t2.b < 3);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 3 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE 1 IN (SELECT 1 FROM t2 WHERE t2.b < 3);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00
+1 PRIMARY t2 ALL NULL NULL NULL NULL 3 100.00 Using where; FirstMatch(t1); Using join buffer (BNL, incremental buffers)
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` semi join (`test`.`t2`) where (`test`.`t2`.`b` < 3)
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 8
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd_next 7
+Handler_update 3
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+#
+# query: UPDATE t1 SET a = 10 WHERE a IN (SELECT b FROM t2 WHERE t1.a < 3)
+# select: SELECT * FROM t1 WHERE a IN (SELECT b FROM t2 WHERE t1.a < 3)
+#
+EXPLAIN UPDATE t1 SET a = 10 WHERE a IN (SELECT b FROM t2 WHERE t1.a < 3);
+id select_type table type possible_keys key key_len ref rows Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 3 Using where
+2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 3 Using where
+EXPLAIN EXTENDED UPDATE t1 SET a = 10 WHERE a IN (SELECT b FROM t2 WHERE t1.a < 3);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 3 100.00 Using where
+Warnings:
+Note 1276 Field or reference 'test.t1.a' of SELECT #2 was resolved in SELECT #1
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a IN (SELECT b FROM t2 WHERE t1.a < 3);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+1 PRIMARY t2 ALL NULL NULL NULL NULL 3 100.00 Using where; FirstMatch(t1); Using join buffer (BNL, incremental buffers)
+Warnings:
+Note 1276 Field or reference 'test.t1.a' of SELECT #2 was resolved in SELECT #1
+Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t2`.`b` = `test`.`t1`.`a`) and (`test`.`t1`.`a` < 3))
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 8
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd_next 11
+Handler_update 2
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+#
+# query: UPDATE t1, t2 SET a = 10 WHERE a IN (SELECT b FROM t2 WHERE t2.b < 3)
+# select: SELECT * FROM t1, t2 WHERE a IN (SELECT b FROM t2 WHERE t2.b < 3)
+#
+EXPLAIN UPDATE t1, t2 SET a = 10 WHERE a IN (SELECT b FROM t2 WHERE t2.b < 3);
+id select_type table type possible_keys key key_len ref rows Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 3 Using where
+1 PRIMARY t2 ALL NULL NULL NULL NULL 3 Using join buffer (BNL, incremental buffers)
+1 PRIMARY t2 ALL NULL NULL NULL NULL 3 Using where; FirstMatch(t2); Using join buffer (BNL, incremental buffers)
+EXPLAIN EXTENDED UPDATE t1, t2 SET a = 10 WHERE a IN (SELECT b FROM t2 WHERE t2.b < 3);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+1 PRIMARY t2 ALL NULL NULL NULL NULL 3 100.00 Using join buffer (BNL, incremental buffers)
+1 PRIMARY t2 ALL NULL NULL NULL NULL 3 100.00 Using where; FirstMatch(t2); Using join buffer (BNL, incremental buffers)
+EXPLAIN EXTENDED SELECT * FROM t1, t2 WHERE a IN (SELECT b FROM t2 WHERE t2.b < 3);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+1 PRIMARY t2 ALL NULL NULL NULL NULL 3 100.00 Using join buffer (BNL, incremental buffers)
+1 PRIMARY t2 ALL NULL NULL NULL NULL 3 100.00 Using where; FirstMatch(t2); Using join buffer (BNL, incremental buffers)
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t1` semi join (`test`.`t2`) join `test`.`t2` where ((`test`.`t2`.`b` = `test`.`t1`.`a`) and (`test`.`t1`.`a` < 3))
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 12
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd_next 31
+Handler_update 2
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+#
+# query: UPDATE t1 t11, (SELECT * FROM t2) t12 SET t11.a = t11.a + 10
+# select: SELECT * FROM t1 t11, (SELECT * FROM t2) t12
+#
+EXPLAIN UPDATE t1 t11, (SELECT * FROM t2) t12 SET t11.a = t11.a + 10;
+id select_type table type possible_keys key key_len ref rows Extra
+1 PRIMARY t11 ALL NULL NULL NULL NULL 3
+1 PRIMARY <derived2> ALL NULL NULL NULL NULL 3 Using join buffer (BNL, incremental buffers)
+2 DERIVED t2 ALL NULL NULL NULL NULL 3
+EXPLAIN EXTENDED UPDATE t1 t11, (SELECT * FROM t2) t12 SET t11.a = t11.a + 10;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t11 ALL NULL NULL NULL NULL 3 100.00
+1 PRIMARY <derived2> ALL NULL NULL NULL NULL 3 100.00 Using join buffer (BNL, incremental buffers)
+2 DERIVED t2 ALL NULL NULL NULL NULL 3 100.00
+EXPLAIN EXTENDED SELECT * FROM t1 t11, (SELECT * FROM t2) t12;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t11 ALL NULL NULL NULL NULL 3 100.00
+1 PRIMARY <derived2> ALL NULL NULL NULL NULL 3 100.00 Using join buffer (BNL, incremental buffers)
+2 DERIVED t2 ALL NULL NULL NULL NULL 3 100.00
+Warnings:
+Note 1003 select `test`.`t11`.`a` AS `a`,`t12`.`b` AS `b` from `test`.`t1` `t11` join (select `test`.`t2`.`b` AS `b` from `test`.`t2`) `t12`
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 12
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd 3
+Handler_read_rnd_next 25
+Handler_update 3
+Handler_write 12
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+#
+# query: UPDATE t1 t11, (SELECT 1 FROM DUAL) t12 SET t11.a = t11.a + 10
+# select: SELECT * FROM t1 t11, (SELECT 1 FROM DUAL) t12
+#
+EXPLAIN UPDATE t1 t11, (SELECT 1 FROM DUAL) t12 SET t11.a = t11.a + 10;
+id select_type table type possible_keys key key_len ref rows Extra
+1 PRIMARY <derived2> system NULL NULL NULL NULL 1
+1 PRIMARY t11 ALL NULL NULL NULL NULL 3
+2 DERIVED NULL NULL NULL NULL NULL NULL NULL No tables used
+EXPLAIN EXTENDED UPDATE t1 t11, (SELECT 1 FROM DUAL) t12 SET t11.a = t11.a + 10;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY <derived2> system NULL NULL NULL NULL 1 100.00
+1 PRIMARY t11 ALL NULL NULL NULL NULL 3 100.00
+2 DERIVED NULL NULL NULL NULL NULL NULL NULL NULL No tables used
+EXPLAIN EXTENDED SELECT * FROM t1 t11, (SELECT 1 FROM DUAL) t12;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY <derived2> system NULL NULL NULL NULL 1 100.00
+1 PRIMARY t11 ALL NULL NULL NULL NULL 3 100.00
+2 DERIVED NULL NULL NULL NULL NULL NULL NULL NULL No tables used
+Warnings:
+Note 1003 select `test`.`t11`.`a` AS `a`,'1' AS `1` from `test`.`t1` `t11`
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_first 1
+Handler_read_rnd_next 5
+# Status of testing query execution:
+Variable_name Value
+Handler_read_first 1
+Handler_read_rnd 3
+Handler_read_rnd_next 9
+Handler_update 3
+Handler_write 4
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+#
+# query: UPDATE t1 t11, (SELECT * FROM t2) t12 SET t11.a = 10 WHERE t11.a > 1
+# select: SELECT * FROM t1 t11, (SELECT * FROM t2) t12 WHERE t11.a > 1
+#
+EXPLAIN UPDATE t1 t11, (SELECT * FROM t2) t12 SET t11.a = 10 WHERE t11.a > 1;
+id select_type table type possible_keys key key_len ref rows Extra
+1 PRIMARY t11 ALL NULL NULL NULL NULL 3 Using where
+1 PRIMARY <derived2> ALL NULL NULL NULL NULL 3 Using join buffer (BNL, incremental buffers)
+2 DERIVED t2 ALL NULL NULL NULL NULL 3
+EXPLAIN EXTENDED UPDATE t1 t11, (SELECT * FROM t2) t12 SET t11.a = 10 WHERE t11.a > 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t11 ALL NULL NULL NULL NULL 3 100.00 Using where
+1 PRIMARY <derived2> ALL NULL NULL NULL NULL 3 100.00 Using join buffer (BNL, incremental buffers)
+2 DERIVED t2 ALL NULL NULL NULL NULL 3 100.00
+EXPLAIN EXTENDED SELECT * FROM t1 t11, (SELECT * FROM t2) t12 WHERE t11.a > 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t11 ALL NULL NULL NULL NULL 3 100.00 Using where
+1 PRIMARY <derived2> ALL NULL NULL NULL NULL 3 100.00 Using join buffer (BNL, incremental buffers)
+2 DERIVED t2 ALL NULL NULL NULL NULL 3 100.00
+Warnings:
+Note 1003 select `test`.`t11`.`a` AS `a`,`t12`.`b` AS `b` from `test`.`t1` `t11` join (select `test`.`t2`.`b` AS `b` from `test`.`t2`) `t12` where (`test`.`t11`.`a` > 1)
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 12
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd_next 16
+Handler_update 2
+Handler_write 3
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+#
+# query: DELETE FROM t1 WHERE a > 1 LIMIT 1
+# select: SELECT * FROM t1 WHERE a > 1 LIMIT 1
+#
+EXPLAIN DELETE FROM t1 WHERE a > 1 LIMIT 1;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where
+EXPLAIN EXTENDED DELETE FROM t1 WHERE a > 1 LIMIT 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a > 1 LIMIT 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`a` > 1) limit 1
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 2
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 1
+Handler_read_rnd_next 2
+
+DROP TABLE t1;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+#
+# query: DELETE FROM t1 WHERE 0
+# select: SELECT * FROM t1 WHERE 0
+#
+EXPLAIN DELETE FROM t1 WHERE 0;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
+EXPLAIN EXTENDED DELETE FROM t1 WHERE 0;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE 0;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where 0
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+# Status of testing query execution:
+Variable_name Value
+
+DROP TABLE t1;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+#
+# query: DELETE FROM t1 USING t1 WHERE 0
+# select: SELECT * FROM t1 WHERE 0
+#
+EXPLAIN DELETE FROM t1 USING t1 WHERE 0;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
+EXPLAIN EXTENDED DELETE FROM t1 USING t1 WHERE 0;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE 0;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where 0
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+# Status of testing query execution:
+Variable_name Value
+
+DROP TABLE t1;
+CREATE TABLE t1 (a INT, b INT, UNIQUE KEY (a), KEY (b));
+INSERT INTO t1 VALUES (3, 3), (7, 7);
+#
+# query: DELETE FROM t1 WHERE a = 3
+# select: SELECT * FROM t1 WHERE a = 3
+#
+EXPLAIN DELETE FROM t1 WHERE a = 3;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 range a,b a 5 NULL 1 Using where
+EXPLAIN EXTENDED DELETE FROM t1 WHERE a = 3;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 range a,b a 5 NULL 1 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a = 3;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 const a a 5 const 1 100.00
+Warnings:
+Note 1003 select '3' AS `a`,'3' AS `b` from `test`.`t1` where 1
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 1
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 1
+Handler_read_key 1
+
+DROP TABLE t1;
+CREATE TABLE t1 (a INT, b INT, UNIQUE KEY (a), KEY (b));
+INSERT INTO t1 VALUES (3, 3), (7, 7);
+#
+# query: DELETE FROM t1 WHERE a < 3
+# select: SELECT * FROM t1 WHERE a < 3
+#
+EXPLAIN DELETE FROM t1 WHERE a < 3;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 range a,b a 5 NULL 1 Using where
+EXPLAIN EXTENDED DELETE FROM t1 WHERE a < 3;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 range a,b a 5 NULL 1 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a < 3;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 range a a 5 NULL 1 100.00 Using index condition
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where (`test`.`t1`.`a` < 3)
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 1
+# Status of testing query execution:
+Variable_name Value
+Handler_read_key 1
+
+DROP TABLE t1;
+CREATE TABLE t1 ( a int PRIMARY KEY );
+#
+# query: DELETE FROM t1 WHERE t1.a > 0 ORDER BY t1.a
+# select: SELECT * FROM t1 WHERE t1.a > 0 ORDER BY t1.a
+#
+EXPLAIN DELETE FROM t1 WHERE t1.a > 0 ORDER BY t1.a;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 1 Using where
+EXPLAIN EXTENDED DELETE FROM t1 WHERE t1.a > 0 ORDER BY t1.a;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 1 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE t1.a > 0 ORDER BY t1.a;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
+Warnings:
+Note 1003 select NULL AS `a` from `test`.`t1` where 0 order by NULL
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_first 1
+Handler_read_rnd_next 1
+# Status of testing query execution:
+Variable_name Value
+Handler_read_key 1
+
+INSERT INTO t1 VALUES (1), (2), (3);
+#
+# query: DELETE FROM t1 WHERE t1.a > 0 ORDER BY t1.a
+# select: SELECT * FROM t1 WHERE t1.a > 0 ORDER BY t1.a
+#
+EXPLAIN DELETE FROM t1 WHERE t1.a > 0 ORDER BY t1.a;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 3 Using where
+EXPLAIN EXTENDED DELETE FROM t1 WHERE t1.a > 0 ORDER BY t1.a;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 3 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE t1.a > 0 ORDER BY t1.a;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 index PRIMARY PRIMARY 4 NULL 3 100.00 Using where; Using index
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`a` > 0) order by `test`.`t1`.`a`
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_first 1
+Handler_read_next 3
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 3
+Handler_read_key 1
+Handler_read_next 3
+
+DROP TABLE t1;
+CREATE TABLE t1(a INT PRIMARY KEY);
+INSERT INTO t1 VALUES (4),(3),(1),(2);
+#
+# query: DELETE FROM t1 WHERE (@a:= a) ORDER BY a LIMIT 1
+# select: SELECT * FROM t1 WHERE (@a:= a) ORDER BY a LIMIT 1
+#
+EXPLAIN DELETE FROM t1 WHERE (@a:= a) ORDER BY a LIMIT 1;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL PRIMARY PRIMARY 4 NULL 4 Using where
+EXPLAIN EXTENDED DELETE FROM t1 WHERE (@a:= a) ORDER BY a LIMIT 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL PRIMARY PRIMARY 4 NULL 4 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE (@a:= a) ORDER BY a LIMIT 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 index NULL PRIMARY 4 NULL 1 400.00 Using where; Using index
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where (@a:=`test`.`t1`.`a`) order by `test`.`t1`.`a` limit 1
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_first 1
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 1
+Handler_read_first 1
+
+DROP TABLE t1;
+CREATE TABLE t1 (a DATE, b TIME, c INT, KEY c(c), KEY b(b), KEY a(a));
+INSERT INTO t1 VALUES (), (), (), (), (), (), (), (), (), ();
+UPDATE t1 SET a = c, b = c;
+#
+# query: DELETE FROM t1 ORDER BY a ASC, b ASC LIMIT 1
+# select: SELECT * FROM t1 ORDER BY a ASC, b ASC LIMIT 1
+#
+EXPLAIN DELETE FROM t1 ORDER BY a ASC, b ASC LIMIT 1;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL c,b,a NULL NULL NULL 10 Using filesort
+EXPLAIN EXTENDED DELETE FROM t1 ORDER BY a ASC, b ASC LIMIT 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL c,b,a NULL NULL NULL 10 100.00 Using filesort
+EXPLAIN EXTENDED SELECT * FROM t1 ORDER BY a ASC, b ASC LIMIT 1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 10 100.00 Using filesort
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t1`.`c` AS `c` from `test`.`t1` order by `test`.`t1`.`a`,`test`.`t1`.`b` limit 1
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 11
+Sort_rows 1
+Sort_scan 1
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 1
+Handler_read_rnd 1
+Handler_read_rnd_next 11
+Sort_rows 10
+Sort_scan 1
+
+DROP TABLE t1;
+CREATE TABLE t1 (a1 INT NOT NULL, b1 INT NOT NULL);
+CREATE TABLE t2 (a2 INT NOT NULL, b2 INT NOT NULL, PRIMARY KEY (a2,b2));
+CREATE TABLE t3 (a3 INT NOT NULL, b3 INT NOT NULL, PRIMARY KEY (a3,b3));
+INSERT INTO t1 VALUES (1,1), (2,1), (1,3);
+INSERT INTO t2 VALUES (1,1), (2,2), (3,3);
+INSERT INTO t3 VALUES (1,1), (2,1), (1,3);
+#
+# query: DELETE t1,t2,t3 FROM t1,t2,t3 WHERE a1=a2 AND b2=a3 AND b1=b3
+# select: SELECT * FROM t1,t2,t3 WHERE a1=a2 AND b2=a3 AND b1=b3
+#
+EXPLAIN DELETE t1,t2,t3 FROM t1,t2,t3 WHERE a1=a2 AND b2=a3 AND b1=b3;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3
+1 SIMPLE t2 ref PRIMARY PRIMARY 4 test.t1.a1 1
+1 SIMPLE t3 eq_ref PRIMARY PRIMARY 8 test.t2.b2,test.t1.b1 1
+EXPLAIN EXTENDED DELETE t1,t2,t3 FROM t1,t2,t3 WHERE a1=a2 AND b2=a3 AND b1=b3;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00
+1 SIMPLE t2 ref PRIMARY PRIMARY 4 test.t1.a1 1 100.00
+1 SIMPLE t3 eq_ref PRIMARY PRIMARY 8 test.t2.b2,test.t1.b1 1 100.00
+EXPLAIN EXTENDED SELECT * FROM t1,t2,t3 WHERE a1=a2 AND b2=a3 AND b1=b3;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00
+1 SIMPLE t2 ref PRIMARY PRIMARY 4 test.t1.a1 1 100.00 Using index
+1 SIMPLE t3 eq_ref PRIMARY PRIMARY 8 test.t2.b2,test.t1.b1 1 100.00 Using index
+Warnings:
+Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`b1` AS `b1`,`test`.`t2`.`a2` AS `a2`,`test`.`t2`.`b2` AS `b2`,`test`.`t3`.`a3` AS `a3`,`test`.`t3`.`b3` AS `b3` from `test`.`t1` join `test`.`t2` join `test`.`t3` where ((`test`.`t3`.`b3` = `test`.`t1`.`b1`) and (`test`.`t3`.`a3` = `test`.`t2`.`b2`) and (`test`.`t2`.`a2` = `test`.`t1`.`a1`))
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 6
+Handler_read_next 3
+Handler_read_rnd_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 8
+Handler_read_key 6
+Handler_read_next 3
+Handler_read_rnd 5
+Handler_read_rnd_next 4
+
+DROP TABLE t1, t2, t3;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (a INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+#
+# query: UPDATE t1 SET a = 10 WHERE a IN (SELECT a FROM t2)
+# select: SELECT * FROM t1 WHERE a IN (SELECT a FROM t2)
+#
+EXPLAIN UPDATE t1 SET a = 10 WHERE a IN (SELECT a FROM t2);
+id select_type table type possible_keys key key_len ref rows Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 3 Using where
+2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 3 Using where
+EXPLAIN EXTENDED UPDATE t1 SET a = 10 WHERE a IN (SELECT a FROM t2);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
+2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 3 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a IN (SELECT a FROM t2);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00
+1 PRIMARY t2 ALL NULL NULL NULL NULL 3 100.00 Using where; FirstMatch(t1); Using join buffer (BNL, incremental buffers)
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` semi join (`test`.`t2`) where (`test`.`t2`.`a` = `test`.`t1`.`a`)
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 8
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd_next 10
+Handler_update 3
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (a1 INT);
+INSERT INTO t1 VALUES (1), (2), (3), (4), (5);
+CREATE TABLE t2 (a2 VARCHAR(10));
+INSERT INTO t2 VALUES (1), (2), (3), (4), (5);
+SET @save_optimizer_switch= @@optimizer_switch;
+SET @@optimizer_switch= 'semijoin=off';
+#
+# query: DELETE FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2)
+# select: SELECT * FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2)
+#
+EXPLAIN DELETE FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2);
+id select_type table type possible_keys key key_len ref rows Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 5 Using where
+2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 5 Using where
+EXPLAIN EXTENDED DELETE FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 5 100.00 Using where
+2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 5 100.00 Using where
+2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where
+Warnings:
+Note 1003 select `test`.`t1`.`a1` AS `a1` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`a1`,<exists>(select 1 from `test`.`t2` where ((`test`.`t2`.`a2` > 2) and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`a2`))))
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 30
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 3
+Handler_read_rnd_next 30
+
+SET @@optimizer_switch= @save_optimizer_switch;
+TRUNCATE t1;
+INSERT INTO t1 VALUES (1), (2), (3), (4), (5);
+#
+# query: DELETE FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2)
+# select: SELECT * FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2)
+#
+EXPLAIN DELETE FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2);
+id select_type table type possible_keys key key_len ref rows Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 5 Using where
+2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 5 Using where
+EXPLAIN EXTENDED DELETE FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 5 100.00 Using where
+2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 5 100.00
+1 PRIMARY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; FirstMatch(t1); Using join buffer (BNL, incremental buffers)
+Warnings:
+Note 1003 select `test`.`t1`.`a1` AS `a1` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t2`.`a2` > 2) and (`test`.`t1`.`a1` = `test`.`t2`.`a2`))
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 12
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 3
+Handler_read_rnd_next 30
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT, j INT);
+INSERT INTO t1 VALUES (1, 1), (2, 2), (3, 3), (4, 4), (5, 5);
+#
+# query: UPDATE t1 SET i = 10
+# select: SELECT * FROM t1
+#
+EXPLAIN UPDATE t1 SET i = 10;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 5
+EXPLAIN EXTENDED UPDATE t1 SET i = 10;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 5 100.00
+EXPLAIN EXTENDED SELECT * FROM t1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 5 100.00
+Warnings:
+Note 1003 select `test`.`t1`.`i` AS `i`,`test`.`t1`.`j` AS `j` from `test`.`t1`
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 6
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd_next 6
+Handler_update 5
+
+DROP TABLE t1;
+CREATE TABLE t1 (i INT, j INT);
+INSERT INTO t1 VALUES (1, 1), (2, 2), (3, 3), (4, 4), (5, 5);
+#
+# query: DELETE FROM t1
+# select: SELECT * FROM t1
+#
+EXPLAIN DELETE FROM t1;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL 5 Using delete_all_rows
+EXPLAIN EXTENDED DELETE FROM t1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL 5 NULL Using delete_all_rows
+EXPLAIN EXTENDED SELECT * FROM t1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 5 100.00
+Warnings:
+Note 1003 select `test`.`t1`.`i` AS `i`,`test`.`t1`.`j` AS `j` from `test`.`t1`
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 6
+# Status of testing query execution:
+Variable_name Value
+
+DROP TABLE t1;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
+INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
+INSERT INTO t2 (a, b, c) SELECT t1.i, t1.i, t1.i FROM t1, t1 x1, t1 x2;
+#
+# query: DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+# select: SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+#
+EXPLAIN DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a a 15 NULL 17602 Using where
+EXPLAIN EXTENDED DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a a 15 NULL 17602 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 index NULL a 15 NULL 5 352040.00 Using where
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2` where (`test`.`t2`.`b` = 10) order by `test`.`t2`.`a`,`test`.`t2`.`c` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_first 1
+Handler_read_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 5
+Handler_read_first 1
+Handler_read_next 4
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (i INT);
+#
+# query: INSERT INTO t2 SELECT * FROM t1
+# select: SELECT * FROM t1
+#
+EXPLAIN INSERT INTO t2 SELECT * FROM t1;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3
+EXPLAIN EXTENDED INSERT INTO t2 SELECT * FROM t1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00
+EXPLAIN EXTENDED SELECT * FROM t1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00
+Warnings:
+Note 1003 select `test`.`t1`.`i` AS `i` from `test`.`t1`
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd_next 4
+Handler_write 3
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (i INT);
+#
+# query: REPLACE INTO t2 SELECT * FROM t1
+# select: SELECT * FROM t1
+#
+EXPLAIN REPLACE INTO t2 SELECT * FROM t1;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3
+EXPLAIN EXTENDED REPLACE INTO t2 SELECT * FROM t1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00
+EXPLAIN EXTENDED SELECT * FROM t1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00
+Warnings:
+Note 1003 select `test`.`t1`.`i` AS `i` from `test`.`t1`
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd_next 4
+Handler_write 3
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+#
+# query: INSERT INTO t1 SET i = 10
+# select:
+#
+EXPLAIN INSERT INTO t1 SET i = 10;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No tables used
+EXPLAIN EXTENDED INSERT INTO t1 SET i = 10;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
+# Status of testing query execution:
+Variable_name Value
+Handler_write 1
+
+DROP TABLE t1;
+CREATE TABLE t1 (i INT);
+#
+# query: REPLACE INTO t1 SET i = 10
+# select:
+#
+EXPLAIN REPLACE INTO t1 SET i = 10;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No tables used
+EXPLAIN EXTENDED REPLACE INTO t1 SET i = 10;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
+# Status of testing query execution:
+Variable_name Value
+Handler_write 1
+
+DROP TABLE t1;
+CREATE TABLE t1 (a INT, i INT PRIMARY KEY);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+#
+# query: DELETE FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+# select: SELECT * FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+#
+EXPLAIN DELETE FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 8 Using where
+EXPLAIN EXTENDED DELETE FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 8 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 8 100.00 Using index condition
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`i` AS `i` from `test`.`t1` where ((`test`.`t1`.`i` > 10) and (`test`.`t1`.`i` <= 18)) order by `test`.`t1`.`i` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 1
+Handler_read_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 5
+Handler_read_key 1
+Handler_read_next 4
+
+DROP TABLE t1;
+CREATE TABLE t1(a INT, i CHAR(2), INDEX(i(1)));
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+#
+# query: DELETE FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+# select: SELECT * FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+#
+EXPLAIN DELETE FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL i NULL NULL NULL 26 Using where; Using filesort
+EXPLAIN EXTENDED DELETE FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL i NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Warning 1713 Cannot use range access on index 'i' due to type or collation conversion on field 'i'
+Warning 1713 Cannot use range access on index 'i' due to type or collation conversion on field 'i'
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ALL i NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Warning 1713 Cannot use range access on index 'i' due to type or collation conversion on field 'i'
+Warning 1713 Cannot use range access on index 'i' due to type or collation conversion on field 'i'
+Warning 1713 Cannot use range access on index 'i' due to type or collation conversion on field 'i'
+Warning 1713 Cannot use range access on index 'i' due to type or collation conversion on field 'i'
+Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`i` AS `i` from `test`.`t1` where ((`test`.`t1`.`i` > 10) and (`test`.`t1`.`i` <= 18)) order by `test`.`t1`.`i` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 27
+Sort_rows 5
+Sort_scan 1
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 5
+Handler_read_rnd 5
+Handler_read_rnd_next 27
+Sort_rows 8
+Sort_scan 1
+
+DROP TABLE t1;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
+INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
+#
+# query: DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+# select: SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+#
+EXPLAIN DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 Using where; Using filesort
+EXPLAIN EXTENDED DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 100.00 Using where; Using filesort
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL NULL NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2` where (`test`.`t2`.`b` = 10) order by `test`.`t2`.`a`,`test`.`t2`.`c` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 27
+Sort_rows 1
+Sort_scan 1
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 1
+Handler_read_rnd 1
+Handler_read_rnd_next 27
+Sort_rows 1
+Sort_scan 1
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
+INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
+INSERT INTO t2 (a, b, c) SELECT t1.i, t1.i, t1.i FROM t1, t1 x1, t1 x2;
+#
+# query: DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+# select: SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+#
+EXPLAIN DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a a 15 NULL 17602 Using where
+EXPLAIN EXTENDED DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a a 15 NULL 17602 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 index NULL a 15 NULL 5 352040.00 Using where
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2` where (`test`.`t2`.`b` = 10) order by `test`.`t2`.`a`,`test`.`t2`.`c` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_first 1
+Handler_read_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 5
+Handler_read_first 1
+Handler_read_next 4
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), d CHAR(2), INDEX (a,b(1),c));
+INSERT INTO t2 SELECT i, i, i, i FROM t1;
+#
+# query: DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+# select: SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+#
+EXPLAIN DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 Using where; Using filesort
+EXPLAIN EXTENDED DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Warning 1713 Cannot use range access on index 'a' due to type or collation conversion on field 'b'
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL NULL NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2` where (`test`.`t2`.`b` = 10) order by `test`.`t2`.`a`,`test`.`t2`.`c` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 27
+Sort_rows 1
+Sort_scan 1
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 1
+Handler_read_rnd 1
+Handler_read_rnd_next 27
+Sort_rows 1
+Sort_scan 1
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), d CHAR(2), INDEX (a,b,c))
+ENGINE=HEAP;
+INSERT INTO t2 SELECT i, i, i, i FROM t1;
+#
+# query: DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+# select: SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+#
+EXPLAIN DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 Using where; Using filesort
+EXPLAIN EXTENDED DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Warning 1713 Cannot use range access on index 'a' due to type or collation conversion on field 'b'
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL NULL NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2` where (`test`.`t2`.`b` = 10) order by `test`.`t2`.`a`,`test`.`t2`.`c` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd 1
+Handler_read_rnd_next 27
+Sort_rows 1
+Sort_scan 1
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 1
+Handler_read_rnd 1
+Handler_read_rnd_next 27
+Sort_rows 1
+Sort_scan 1
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (i INT, key1 INT, key2 INT, INDEX (key1), INDEX (key2))
+ENGINE= MyISAM;
+INSERT INTO t2 (key1, key2) SELECT i, i FROM t1;
+#
+# query: DELETE FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1
+# select: SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1
+#
+EXPLAIN DELETE FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 index_merge key1,key2 key1,key2 5,5 NULL 7 Using sort_union(key1,key2); Using where; Using filesort
+EXPLAIN EXTENDED DELETE FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 index_merge key1,key2 key1,key2 5,5 NULL 7 100.00 Using sort_union(key1,key2); Using where; Using filesort
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 index_merge key1,key2 key1,key2 5,5 NULL 7 100.00 Using sort_union(key1,key2); Using where; Using filesort
+Warnings:
+Note 1003 select `test`.`t2`.`i` AS `i`,`test`.`t2`.`key1` AS `key1`,`test`.`t2`.`key2` AS `key2` from `test`.`t2` where ((`test`.`t2`.`key1` < 13) or (`test`.`t2`.`key2` < 14)) order by `test`.`t2`.`key1`
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 2
+Handler_read_next 7
+Handler_read_rnd 4
+Sort_range 1
+Sort_rows 4
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 4
+Handler_read_key 2
+Handler_read_next 7
+Handler_read_rnd 8
+Sort_range 1
+Sort_rows 4
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, i INT PRIMARY KEY);
+INSERT INTO t2 (i) SELECT i FROM t1;
+#
+# query: DELETE FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5
+# select: SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5
+#
+EXPLAIN DELETE FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 8 Using where
+EXPLAIN EXTENDED DELETE FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 8 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 8 100.00 Using index condition
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`i` AS `i` from `test`.`t2` where ((`test`.`t2`.`i` > 10) and (`test`.`t2`.`i` <= 18)) order by `test`.`t2`.`i` desc limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 1
+Handler_read_prev 4
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 5
+Handler_read_key 1
+Handler_read_prev 4
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), INDEX (a, b));
+INSERT INTO t2 SELECT i, i, i FROM t1;
+#
+# query: DELETE FROM t2 ORDER BY a, b DESC LIMIT 5
+# select: SELECT * FROM t2 ORDER BY a, b DESC LIMIT 5
+#
+EXPLAIN DELETE FROM t2 ORDER BY a, b DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 Using filesort
+EXPLAIN EXTENDED DELETE FROM t2 ORDER BY a, b DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 100.00 Using filesort
+EXPLAIN EXTENDED SELECT * FROM t2 ORDER BY a, b DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL NULL NULL NULL NULL 26 100.00 Using filesort
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t2` order by `test`.`t2`.`a`,`test`.`t2`.`b` desc limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 27
+Sort_rows 5
+Sort_scan 1
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 5
+Handler_read_rnd 5
+Handler_read_rnd_next 27
+Sort_rows 26
+Sort_scan 1
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c INT, INDEX (a, b));
+INSERT INTO t2 (a, b) SELECT i, i FROM t1;
+INSERT INTO t2 (a, b) SELECT t1.i, t1.i FROM t1, t1 x1, t1 x2;
+#
+# query: DELETE FROM t2 ORDER BY a DESC, b DESC LIMIT 5
+# select: SELECT * FROM t2 ORDER BY a DESC, b DESC LIMIT 5
+#
+EXPLAIN DELETE FROM t2 ORDER BY a DESC, b DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a a 6 NULL 5
+EXPLAIN EXTENDED DELETE FROM t2 ORDER BY a DESC, b DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a a 6 NULL 5 100.00
+EXPLAIN EXTENDED SELECT * FROM t2 ORDER BY a DESC, b DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 index NULL a 6 NULL 5 352040.00
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t2` order by `test`.`t2`.`a` desc,`test`.`t2`.`b` desc limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_last 1
+Handler_read_prev 4
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 5
+Handler_read_last 1
+Handler_read_prev 4
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, i INT PRIMARY KEY);
+INSERT INTO t2 (i) SELECT i FROM t1;
+#
+# query: UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+# select: SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+#
+EXPLAIN UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 8 Using where
+EXPLAIN EXTENDED UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 8 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 8 100.00 Using index condition
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`i` AS `i` from `test`.`t2` where ((`test`.`t2`.`i` > 10) and (`test`.`t2`.`i` <= 18)) order by `test`.`t2`.`i` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 1
+Handler_read_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_read_key 1
+Handler_read_next 4
+Handler_read_rnd 5
+Handler_update 5
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, i CHAR(2), INDEX(i(1)));
+INSERT INTO t2 (i) SELECT i FROM t1;
+#
+# query: UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+# select: SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+#
+EXPLAIN UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL i NULL NULL NULL 26 Using where; Using filesort
+EXPLAIN EXTENDED UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL i NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Warning 1713 Cannot use range access on index 'i' due to type or collation conversion on field 'i'
+Warning 1713 Cannot use range access on index 'i' due to type or collation conversion on field 'i'
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL i NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Warning 1713 Cannot use range access on index 'i' due to type or collation conversion on field 'i'
+Warning 1713 Cannot use range access on index 'i' due to type or collation conversion on field 'i'
+Warning 1713 Cannot use range access on index 'i' due to type or collation conversion on field 'i'
+Warning 1713 Cannot use range access on index 'i' due to type or collation conversion on field 'i'
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`i` AS `i` from `test`.`t2` where ((`test`.`t2`.`i` > 10) and (`test`.`t2`.`i` <= 18)) order by `test`.`t2`.`i` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 27
+Sort_rows 5
+Sort_scan 1
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd 5
+Handler_read_rnd_next 27
+Handler_update 5
+Sort_rows 5
+Sort_scan 1
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
+INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
+#
+# query: UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5
+# select: SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+#
+EXPLAIN UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 Using where; Using filesort
+EXPLAIN EXTENDED UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 100.00 Using where; Using filesort
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL NULL NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2` where (`test`.`t2`.`b` = 10) order by `test`.`t2`.`a`,`test`.`t2`.`c` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 27
+Sort_rows 1
+Sort_scan 1
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd 1
+Handler_read_rnd_next 27
+Handler_update 1
+Sort_rows 1
+Sort_scan 1
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
+INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
+INSERT INTO t2 (a, b, c) SELECT t1.i, t1.i, t1.i FROM t1, t1 x1, t1 x2;
+#
+# query: UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5
+# select: SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+#
+EXPLAIN UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a a 15 NULL 17602 Using where
+EXPLAIN EXTENDED UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a a 15 NULL 17602 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 index NULL a 15 NULL 5 352040.00 Using where
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2` where (`test`.`t2`.`b` = 10) order by `test`.`t2`.`a`,`test`.`t2`.`c` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_first 1
+Handler_read_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_read_first 1
+Handler_read_next 4
+Handler_read_rnd 5
+Handler_update 5
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), d CHAR(2), INDEX (a,b(1),c));
+INSERT INTO t2 SELECT i, i, i, i FROM t1;
+#
+# query: UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5
+# select: SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+#
+EXPLAIN UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 Using where; Using filesort
+EXPLAIN EXTENDED UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Warning 1713 Cannot use range access on index 'a' due to type or collation conversion on field 'b'
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL NULL NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2` where (`test`.`t2`.`b` = 10) order by `test`.`t2`.`a`,`test`.`t2`.`c` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 27
+Sort_rows 1
+Sort_scan 1
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd 1
+Handler_read_rnd_next 27
+Sort_rows 1
+Sort_scan 1
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), d CHAR(2), INDEX (a,b,c))
+ENGINE=HEAP;
+INSERT INTO t2 SELECT i, i, i, i FROM t1;
+#
+# query: UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5
+# select: SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+#
+EXPLAIN UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 Using where; Using filesort
+EXPLAIN EXTENDED UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Warning 1713 Cannot use range access on index 'a' due to type or collation conversion on field 'b'
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL NULL NULL NULL NULL 26 100.00 Using where; Using filesort
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t2` where (`test`.`t2`.`b` = 10) order by `test`.`t2`.`a`,`test`.`t2`.`c` limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd 1
+Handler_read_rnd_next 27
+Sort_rows 1
+Sort_scan 1
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd 1
+Handler_read_rnd_next 27
+Sort_rows 1
+Sort_scan 1
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (i INT, key1 INT, key2 INT, INDEX (key1), INDEX (key2))
+ENGINE= MyISAM;
+INSERT INTO t2 (key1, key2) SELECT i, i FROM t1;
+#
+# query: UPDATE t2 SET i = 123 WHERE key1 < 13 or key2 < 14 ORDER BY key1
+# select: SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1
+#
+EXPLAIN UPDATE t2 SET i = 123 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 index_merge key1,key2 key1,key2 5,5 NULL 7 Using sort_union(key1,key2); Using where; Using filesort
+EXPLAIN EXTENDED UPDATE t2 SET i = 123 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 index_merge key1,key2 key1,key2 5,5 NULL 7 100.00 Using sort_union(key1,key2); Using where; Using filesort
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 index_merge key1,key2 key1,key2 5,5 NULL 7 100.00 Using sort_union(key1,key2); Using where; Using filesort
+Warnings:
+Note 1003 select `test`.`t2`.`i` AS `i`,`test`.`t2`.`key1` AS `key1`,`test`.`t2`.`key2` AS `key2` from `test`.`t2` where ((`test`.`t2`.`key1` < 13) or (`test`.`t2`.`key2` < 14)) order by `test`.`t2`.`key1`
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 2
+Handler_read_next 7
+Handler_read_rnd 4
+Sort_range 1
+Sort_rows 4
+# Status of testing query execution:
+Variable_name Value
+Handler_read_key 2
+Handler_read_next 7
+Handler_read_rnd 8
+Handler_update 4
+Sort_range 1
+Sort_rows 4
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, i INT PRIMARY KEY);
+INSERT INTO t2 (i) SELECT i FROM t1;
+#
+# query: UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5
+# select: SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5
+#
+EXPLAIN UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 8 Using where
+EXPLAIN EXTENDED UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 8 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 8 100.00 Using index condition
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`i` AS `i` from `test`.`t2` where ((`test`.`t2`.`i` > 10) and (`test`.`t2`.`i` <= 18)) order by `test`.`t2`.`i` desc limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 1
+Handler_read_prev 4
+# Status of testing query execution:
+Variable_name Value
+Handler_read_key 1
+Handler_read_prev 4
+Handler_read_rnd 5
+Handler_update 5
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), INDEX (a, b));
+INSERT INTO t2 SELECT i, i, i FROM t1;
+#
+# query: UPDATE t2 SET c = 10 ORDER BY a, b DESC LIMIT 5
+# select: SELECT * FROM t2 ORDER BY a, b DESC LIMIT 5
+#
+EXPLAIN UPDATE t2 SET c = 10 ORDER BY a, b DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 Using filesort
+EXPLAIN EXTENDED UPDATE t2 SET c = 10 ORDER BY a, b DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a NULL NULL NULL 26 100.00 Using filesort
+EXPLAIN EXTENDED SELECT * FROM t2 ORDER BY a, b DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL NULL NULL NULL NULL 26 100.00 Using filesort
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t2` order by `test`.`t2`.`a`,`test`.`t2`.`b` desc limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_rnd_next 27
+Sort_rows 5
+Sort_scan 1
+# Status of testing query execution:
+Variable_name Value
+Handler_read_rnd 5
+Handler_read_rnd_next 27
+Handler_update 4
+Sort_rows 5
+Sort_scan 1
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+(20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+(30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c INT, INDEX (a, b));
+INSERT INTO t2 (a, b) SELECT i, i FROM t1;
+INSERT INTO t2 (a, b) SELECT t1.i, t1.i FROM t1, t1 x1, t1 x2;
+#
+# query: UPDATE t2 SET c = 10 ORDER BY a DESC, b DESC LIMIT 5
+# select: SELECT * FROM t2 ORDER BY a DESC, b DESC LIMIT 5
+#
+EXPLAIN UPDATE t2 SET c = 10 ORDER BY a DESC, b DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ALL a a 6 NULL 5
+EXPLAIN EXTENDED UPDATE t2 SET c = 10 ORDER BY a DESC, b DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 ALL a a 6 NULL 5 100.00
+EXPLAIN EXTENDED SELECT * FROM t2 ORDER BY a DESC, b DESC LIMIT 5;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 index NULL a 6 NULL 5 352040.00
+Warnings:
+Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t2` order by `test`.`t2`.`a` desc,`test`.`t2`.`b` desc limit 5
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_last 1
+Handler_read_prev 4
+# Status of testing query execution:
+Variable_name Value
+Handler_read_last 1
+Handler_read_prev 4
+Handler_read_rnd 5
+Handler_update 5
+
+DROP TABLE t1, t2;
+CREATE TABLE t1 (
+pk INT NOT NULL AUTO_INCREMENT,
+c1_idx CHAR(1) DEFAULT 'y',
+c2 INT,
+PRIMARY KEY (pk),
+INDEX c1_idx (c1_idx)
+) ENGINE=InnoDB;
+INSERT INTO t1 VALUES (1,'y',1), (2,'n',2), (3,'y',3), (4,'n',4);
+#
+# query: UPDATE t1 SET c2 = 0 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2
+# select: SELECT * FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2
+#
+EXPLAIN UPDATE t1 SET c2 = 0 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 range PRIMARY,c1_idx c1_idx 2 NULL 2 Using where
+EXPLAIN EXTENDED UPDATE t1 SET c2 = 0 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 range PRIMARY,c1_idx c1_idx 2 NULL 2 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ref c1_idx c1_idx 2 const 2 100.00 Using index condition; Using where
+Warnings:
+Note 1003 select `test`.`t1`.`pk` AS `pk`,`test`.`t1`.`c1_idx` AS `c1_idx`,`test`.`t1`.`c2` AS `c2` from `test`.`t1` where (`test`.`t1`.`c1_idx` = 'y') order by `test`.`t1`.`pk` desc limit 2
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 5
+Handler_read_prev 1
+# Status of testing query execution:
+Variable_name Value
+Handler_read_key 8
+Handler_read_prev 1
+Handler_read_rnd 2
+Handler_update 2
+
+#
+# query: DELETE FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2
+# select: SELECT * FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2
+#
+EXPLAIN DELETE FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 range PRIMARY,c1_idx c1_idx 2 NULL 2 Using where
+EXPLAIN EXTENDED DELETE FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 range PRIMARY,c1_idx c1_idx 2 NULL 2 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 ref c1_idx c1_idx 2 const 2 100.00 Using index condition; Using where
+Warnings:
+Note 1003 select `test`.`t1`.`pk` AS `pk`,`test`.`t1`.`c1_idx` AS `c1_idx`,`test`.`t1`.`c2` AS `c2` from `test`.`t1` where (`test`.`t1`.`c1_idx` = 'y') order by `test`.`t1`.`pk` desc limit 2
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 5
+Handler_read_prev 1
+# Status of testing query execution:
+Variable_name Value
+Handler_delete 2
+Handler_read_key 5
+Handler_read_prev 1
+
+DROP TABLE t1;
+CREATE TABLE t1 (a INT AUTO_INCREMENT PRIMARY KEY);
+INSERT INTO t1 VALUES (),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),();
+#
+# query: UPDATE t1 SET a=a+10 WHERE a > 34
+# select: SELECT * FROM t1 WHERE a > 34
+#
+EXPLAIN UPDATE t1 SET a=a+10 WHERE a > 34;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 3 Using where
+EXPLAIN EXTENDED UPDATE t1 SET a=a+10 WHERE a > 34;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 3 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE a > 34;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 3 100.00 Using where; Using index
+Warnings:
+Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`a` > 34)
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 1
+Handler_read_next 2
+# Status of testing query execution:
+Variable_name Value
+Handler_read_key 1
+Handler_read_next 2
+Handler_read_rnd 2
+Handler_update 2
+
+DROP TABLE t1;
+CREATE TABLE t1 (c1 INT, c2 INT, c3 INT);
+CREATE TABLE t2 (c1 INT, c2 INT);
+INSERT INTO t1 VALUES (1, 1, 10), (2, 2, 20);
+#
+# query: UPDATE t1 LEFT JOIN t2 ON t1.c1 = t2.c1 SET t2.c2 = 10
+# select: SELECT * FROM t1 LEFT JOIN t2 ON t1.c1 = t2.c1
+#
+EXPLAIN UPDATE t1 LEFT JOIN t2 ON t1.c1 = t2.c1 SET t2.c2 = 10;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 system NULL NULL NULL NULL 0 const row not found
+1 SIMPLE t1 ALL NULL NULL NULL NULL 2
+EXPLAIN EXTENDED UPDATE t1 LEFT JOIN t2 ON t1.c1 = t2.c1 SET t2.c2 = 10;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 system NULL NULL NULL NULL 0 0.00 const row not found
+1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00
+EXPLAIN EXTENDED SELECT * FROM t1 LEFT JOIN t2 ON t1.c1 = t2.c1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 system NULL NULL NULL NULL 0 0.00 const row not found
+1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00
+Warnings:
+Note 1003 select `test`.`t1`.`c1` AS `c1`,`test`.`t1`.`c2` AS `c2`,`test`.`t1`.`c3` AS `c3`,NULL AS `c1`,NULL AS `c2` from `test`.`t1`
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_first 1
+Handler_read_rnd_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_read_first 1
+Handler_read_rnd_next 4
+
+#
+# query: UPDATE t1 LEFT JOIN t2 ON t1.c1 = t2.c1 SET t2.c2 = 10 WHERE t1.c3 = 10
+# select: SELECT * FROM t1 LEFT JOIN t2 ON t1.c1 = t2.c1 WHERE t1.c3 = 10
+#
+EXPLAIN UPDATE t1 LEFT JOIN t2 ON t1.c1 = t2.c1 SET t2.c2 = 10 WHERE t1.c3 = 10;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 system NULL NULL NULL NULL 0 const row not found
+1 SIMPLE t1 ALL NULL NULL NULL NULL 2 Using where
+EXPLAIN EXTENDED UPDATE t1 LEFT JOIN t2 ON t1.c1 = t2.c1 SET t2.c2 = 10 WHERE t1.c3 = 10;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 system NULL NULL NULL NULL 0 0.00 const row not found
+1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00 Using where
+EXPLAIN EXTENDED SELECT * FROM t1 LEFT JOIN t2 ON t1.c1 = t2.c1 WHERE t1.c3 = 10;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 SIMPLE t2 system NULL NULL NULL NULL 0 0.00 const row not found
+1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00 Using where
+Warnings:
+Note 1003 select `test`.`t1`.`c1` AS `c1`,`test`.`t1`.`c2` AS `c2`,`test`.`t1`.`c3` AS `c3`,NULL AS `c1`,NULL AS `c2` from `test`.`t1` where (`test`.`t1`.`c3` = 10)
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_first 1
+Handler_read_rnd_next 4
+# Status of testing query execution:
+Variable_name Value
+Handler_read_first 1
+Handler_read_rnd_next 4
+
+DROP TABLE t1, t2;
+CREATE TABLE t1(f1 INT, f2 INT);
+CREATE TABLE t2(f3 INT, f4 INT);
+CREATE INDEX IDX ON t2(f3);
+INSERT INTO t1 VALUES(1,0),(2,0);
+INSERT INTO t2 VALUES(1,1),(2,2);
+#
+# query: UPDATE t1 SET t1.f2=(SELECT MAX(t2.f4) FROM t2 WHERE t2.f3=t1.f1)
+# select: SELECT (SELECT MAX(t2.f4) FROM t2 WHERE t2.f3=t1.f1) FROM t1
+#
+EXPLAIN UPDATE t1 SET t1.f2=(SELECT MAX(t2.f4) FROM t2 WHERE t2.f3=t1.f1);
+id select_type table type possible_keys key key_len ref rows Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 2
+2 DEPENDENT SUBQUERY t2 ref IDX IDX 5 test.t1.f1 2
+EXPLAIN EXTENDED UPDATE t1 SET t1.f2=(SELECT MAX(t2.f4) FROM t2 WHERE t2.f3=t1.f1);
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 2 100.00
+2 DEPENDENT SUBQUERY t2 ref IDX IDX 5 test.t1.f1 2 100.00
+Warnings:
+Note 1276 Field or reference 'test.t1.f1' of SELECT #2 was resolved in SELECT #1
+EXPLAIN EXTENDED SELECT (SELECT MAX(t2.f4) FROM t2 WHERE t2.f3=t1.f1) FROM t1;
+id select_type table type possible_keys key key_len ref rows filtered Extra
+1 PRIMARY t1 ALL NULL NULL NULL NULL 2 100.00
+2 DEPENDENT SUBQUERY t2 ref IDX IDX 5 test.t1.f1 2 100.00
+Warnings:
+Note 1276 Field or reference 'test.t1.f1' of SELECT #2 was resolved in SELECT #1
+Note 1003 select (select max(`test`.`t2`.`f4`) from `test`.`t2` where (`test`.`t2`.`f3` = `test`.`t1`.`f1`)) AS `(SELECT MAX(t2.f4) FROM t2 WHERE t2.f3=t1.f1)` from `test`.`t1`
+# Status of "equivalent" SELECT query execution:
+Variable_name Value
+Handler_read_key 2
+Handler_read_next 2
+Handler_read_rnd_next 3
+# Status of testing query execution:
+Variable_name Value
+Handler_read_key 2
+Handler_read_next 2
+Handler_read_rnd_next 3
+Handler_update 2
+
+DROP TABLE t1, t2;
+CREATE TABLE t1(a INT);
+INSERT INTO t1 VALUES (1);
+SET @a = NULL;
+EXPLAIN DELETE FROM t1 WHERE (@a:= a);
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ALL NULL NULL NULL NULL 1 Using where
+DROP TABLE t1;
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+DELETE FROM t1 USING t1 WHERE uknown_column = 12345;
+ERROR 42S22: Unknown column 'uknown_column' in 'where clause'
+EXPLAIN EXTENDED DELETE FROM t1 USING t1 WHERE uknown_column = 12345;
+ERROR 42S22: Unknown column 'uknown_column' in 'where clause'
+DROP TABLE t1;
+CREATE TABLE t1(f1 INT);
+EXPLAIN EXTENDED UPDATE t1 SET f2=1 ORDER BY f2;
+ERROR 42S22: Unknown column 'f2' in 'order clause'
+UPDATE t1 SET f2=1 ORDER BY f2;
+ERROR 42S22: Unknown column 'f2' in 'order clause'
+DROP TABLE t1;
+CREATE TABLE t1 ( a INT, KEY( a ) );
+INSERT INTO t1 VALUES (0), (1);
+CREATE VIEW v1 AS SELECT t11.a, t12.a AS b FROM t1 t11, t1 t12;
+SET SESSION sql_safe_updates = 1;
+EXPLAIN EXTENDED UPDATE IGNORE v1 SET a = 1;
+ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column
+UPDATE IGNORE v1 SET a = 1;
+ERROR HY000: You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column
+SET SESSION sql_safe_updates = DEFAULT;
+DROP TABLE t1;
+DROP VIEW v1;
=== added file 'mysql-test/t/explain_non_select.test'
--- a/mysql-test/t/explain_non_select.test 1970-01-01 00:00:00 +0000
+++ b/mysql-test/t/explain_non_select.test 2011-04-01 13:53:57 +0000
@@ -0,0 +1,550 @@
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+--let $query = UPDATE t1 SET a = 10 WHERE a < 10
+--let $select = SELECT * FROM t1 WHERE a < 10
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+--let $query = DELETE FROM t1 WHERE a < 10
+--let $select = SELECT * FROM t1 WHERE a < 10
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+--let $query = DELETE FROM t1 USING t1 WHERE a = 1
+--let $select = SELECT * FROM t1 WHERE a = 1
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+--let $query = UPDATE t1, t2 SET t1.a = 10 WHERE t1.a = 1
+--let $select = SELECT * FROM t1, t2 WHERE t1.a = 1
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+--let $query = UPDATE t1 t11, (SELECT * FROM t2) t12 SET t11.a = 10 WHERE t11.a = 1
+--let $select = SELECT * FROM t1 t11, (SELECT * FROM t2) t12 WHERE t11.a = 1
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+--let $query = UPDATE t1 SET a = 10 WHERE 1 IN (SELECT 1 FROM t2 WHERE t2.b < 3)
+--let $select = SELECT * FROM t1 WHERE 1 IN (SELECT 1 FROM t2 WHERE t2.b < 3)
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+--let $query = UPDATE t1 SET a = 10 WHERE a IN (SELECT b FROM t2 WHERE t1.a < 3)
+--let $select = SELECT * FROM t1 WHERE a IN (SELECT b FROM t2 WHERE t1.a < 3)
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+--let $query = UPDATE t1, t2 SET a = 10 WHERE a IN (SELECT b FROM t2 WHERE t2.b < 3)
+--let $select = SELECT * FROM t1, t2 WHERE a IN (SELECT b FROM t2 WHERE t2.b < 3)
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+--let $query = UPDATE t1 t11, (SELECT * FROM t2) t12 SET t11.a = t11.a + 10
+--let $select = SELECT * FROM t1 t11, (SELECT * FROM t2) t12
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+--let $query = UPDATE t1 t11, (SELECT 1 FROM DUAL) t12 SET t11.a = t11.a + 10
+--let $select = SELECT * FROM t1 t11, (SELECT 1 FROM DUAL) t12
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (b INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+--let $query = UPDATE t1 t11, (SELECT * FROM t2) t12 SET t11.a = 10 WHERE t11.a > 1
+--let $select = SELECT * FROM t1 t11, (SELECT * FROM t2) t12 WHERE t11.a > 1
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+--let $query = DELETE FROM t1 WHERE a > 1 LIMIT 1
+--let $select = SELECT * FROM t1 WHERE a > 1 LIMIT 1
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+--let $query = DELETE FROM t1 WHERE 0
+--let $select = SELECT * FROM t1 WHERE 0
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+--let $query = DELETE FROM t1 USING t1 WHERE 0
+--let $select = SELECT * FROM t1 WHERE 0
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+
+CREATE TABLE t1 (a INT, b INT, UNIQUE KEY (a), KEY (b));
+INSERT INTO t1 VALUES (3, 3), (7, 7);
+--let $query = DELETE FROM t1 WHERE a = 3
+--let $select = SELECT * FROM t1 WHERE a = 3
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT, b INT, UNIQUE KEY (a), KEY (b));
+INSERT INTO t1 VALUES (3, 3), (7, 7);
+--let $query = DELETE FROM t1 WHERE a < 3
+--let $select = SELECT * FROM t1 WHERE a < 3
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 ( a int PRIMARY KEY );
+--let $query = DELETE FROM t1 WHERE t1.a > 0 ORDER BY t1.a
+--let $select = SELECT * FROM t1 WHERE t1.a > 0 ORDER BY t1.a
+--source include/explain_non_select.inc
+INSERT INTO t1 VALUES (1), (2), (3);
+--let $query = DELETE FROM t1 WHERE t1.a > 0 ORDER BY t1.a
+--let $select = SELECT * FROM t1 WHERE t1.a > 0 ORDER BY t1.a
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1(a INT PRIMARY KEY);
+INSERT INTO t1 VALUES (4),(3),(1),(2);
+--let $query = DELETE FROM t1 WHERE (@a:= a) ORDER BY a LIMIT 1
+--let $select = SELECT * FROM t1 WHERE (@a:= a) ORDER BY a LIMIT 1
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (a DATE, b TIME, c INT, KEY c(c), KEY b(b), KEY a(a));
+INSERT INTO t1 VALUES (), (), (), (), (), (), (), (), (), ();
+UPDATE t1 SET a = c, b = c;
+--let $query = DELETE FROM t1 ORDER BY a ASC, b ASC LIMIT 1
+--let $select = SELECT * FROM t1 ORDER BY a ASC, b ASC LIMIT 1
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (a1 INT NOT NULL, b1 INT NOT NULL);
+CREATE TABLE t2 (a2 INT NOT NULL, b2 INT NOT NULL, PRIMARY KEY (a2,b2));
+CREATE TABLE t3 (a3 INT NOT NULL, b3 INT NOT NULL, PRIMARY KEY (a3,b3));
+INSERT INTO t1 VALUES (1,1), (2,1), (1,3);
+INSERT INTO t2 VALUES (1,1), (2,2), (3,3);
+INSERT INTO t3 VALUES (1,1), (2,1), (1,3);
+--let $query = DELETE t1,t2,t3 FROM t1,t2,t3 WHERE a1=a2 AND b2=a3 AND b1=b3
+--let $select = SELECT * FROM t1,t2,t3 WHERE a1=a2 AND b2=a3 AND b1=b3
+--source include/explain_non_select.inc
+DROP TABLE t1, t2, t3;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (a INT);
+INSERT INTO t2 VALUES (1), (2), (3);
+--let $query = UPDATE t1 SET a = 10 WHERE a IN (SELECT a FROM t2)
+--let $select = SELECT * FROM t1 WHERE a IN (SELECT a FROM t2)
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (a1 INT);
+INSERT INTO t1 VALUES (1), (2), (3), (4), (5);
+CREATE TABLE t2 (a2 VARCHAR(10));
+INSERT INTO t2 VALUES (1), (2), (3), (4), (5);
+SET @save_optimizer_switch= @@optimizer_switch;
+SET @@optimizer_switch= 'semijoin=off';
+--let $query = DELETE FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2)
+--let $select = SELECT * FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2)
+--source include/explain_non_select.inc
+SET @@optimizer_switch= @save_optimizer_switch;
+TRUNCATE t1;
+INSERT INTO t1 VALUES (1), (2), (3), (4), (5);
+--let $query = DELETE FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2)
+--let $select = SELECT * FROM t1 WHERE a1 IN (SELECT a2 FROM t2 WHERE a2 > 2)
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT, j INT);
+INSERT INTO t1 VALUES (1, 1), (2, 2), (3, 3), (4, 4), (5, 5);
+--let $query = UPDATE t1 SET i = 10
+--let $select = SELECT * FROM t1
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (i INT, j INT);
+INSERT INTO t1 VALUES (1, 1), (2, 2), (3, 3), (4, 4), (5, 5);
+--let $query = DELETE FROM t1
+--let $select = SELECT * FROM t1
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
+INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
+INSERT INTO t2 (a, b, c) SELECT t1.i, t1.i, t1.i FROM t1, t1 x1, t1 x2;
+--let $query = DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--let $select = SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (i INT);
+--let $query = INSERT INTO t2 SELECT * FROM t1
+--let $select = SELECT * FROM t1
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+CREATE TABLE t2 (i INT);
+--let $query = REPLACE INTO t2 SELECT * FROM t1
+--let $select = SELECT * FROM t1
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+--let $query = INSERT INTO t1 SET i = 10
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (i INT);
+--let $query = REPLACE INTO t1 SET i = 10
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT, i INT PRIMARY KEY);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+--let $query = DELETE FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+--let $select = SELECT * FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1(a INT, i CHAR(2), INDEX(i(1)));
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+--let $query = DELETE FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+--let $select = SELECT * FROM t1 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
+INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
+--let $query = DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--let $select = SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
+INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
+INSERT INTO t2 (a, b, c) SELECT t1.i, t1.i, t1.i FROM t1, t1 x1, t1 x2;
+--let $query = DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--let $select = SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), d CHAR(2), INDEX (a,b(1),c));
+INSERT INTO t2 SELECT i, i, i, i FROM t1;
+--let $query = DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--let $select = SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), d CHAR(2), INDEX (a,b,c))
+ ENGINE=HEAP;
+INSERT INTO t2 SELECT i, i, i, i FROM t1;
+--let $query = DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--let $select = SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (i INT, key1 INT, key2 INT, INDEX (key1), INDEX (key2))
+ ENGINE= MyISAM;
+INSERT INTO t2 (key1, key2) SELECT i, i FROM t1;
+--let $query = DELETE FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1
+--let $select = SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, i INT PRIMARY KEY);
+INSERT INTO t2 (i) SELECT i FROM t1;
+--let $query = DELETE FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5
+--let $select = SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 (i) VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), INDEX (a, b));
+INSERT INTO t2 SELECT i, i, i FROM t1;
+--let $query = DELETE FROM t2 ORDER BY a, b DESC LIMIT 5
+--let $select = SELECT * FROM t2 ORDER BY a, b DESC LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c INT, INDEX (a, b));
+INSERT INTO t2 (a, b) SELECT i, i FROM t1;
+INSERT INTO t2 (a, b) SELECT t1.i, t1.i FROM t1, t1 x1, t1 x2;
+--let $query = DELETE FROM t2 ORDER BY a DESC, b DESC LIMIT 5
+--let $select = SELECT * FROM t2 ORDER BY a DESC, b DESC LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, i INT PRIMARY KEY);
+INSERT INTO t2 (i) SELECT i FROM t1;
+--let $query = UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+--let $select = SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, i CHAR(2), INDEX(i(1)));
+INSERT INTO t2 (i) SELECT i FROM t1;
+--let $query = UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+--let $select = SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
+INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
+--let $query = UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5
+--let $select = SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
+INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
+INSERT INTO t2 (a, b, c) SELECT t1.i, t1.i, t1.i FROM t1, t1 x1, t1 x2;
+--let $query = UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5
+--let $select = SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), d CHAR(2), INDEX (a,b(1),c));
+INSERT INTO t2 SELECT i, i, i, i FROM t1;
+--let $query = UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5
+--let $select = SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), d CHAR(2), INDEX (a,b,c))
+ ENGINE=HEAP;
+INSERT INTO t2 SELECT i, i, i, i FROM t1;
+--let $query = UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5
+--let $select = SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (i INT, key1 INT, key2 INT, INDEX (key1), INDEX (key2))
+ ENGINE= MyISAM;
+INSERT INTO t2 (key1, key2) SELECT i, i FROM t1;
+--let $query = UPDATE t2 SET i = 123 WHERE key1 < 13 or key2 < 14 ORDER BY key1
+--let $select = SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2(a INT, i INT PRIMARY KEY);
+INSERT INTO t2 (i) SELECT i FROM t1;
+--let $query = UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5
+--let $select = SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), INDEX (a, b));
+INSERT INTO t2 SELECT i, i, i FROM t1;
+--let $query = UPDATE t2 SET c = 10 ORDER BY a, b DESC LIMIT 5
+--let $select = SELECT * FROM t2 ORDER BY a, b DESC LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
+ (20),(21),(22),(23),(24),(25),(26),(27),(28),(29),
+ (30),(31),(32),(33),(34),(35);
+CREATE TABLE t2 (a CHAR(2), b CHAR(2), c INT, INDEX (a, b));
+INSERT INTO t2 (a, b) SELECT i, i FROM t1;
+INSERT INTO t2 (a, b) SELECT t1.i, t1.i FROM t1, t1 x1, t1 x2;
+--let $query = UPDATE t2 SET c = 10 ORDER BY a DESC, b DESC LIMIT 5
+--let $select = SELECT * FROM t2 ORDER BY a DESC, b DESC LIMIT 5
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+--disable_warnings
+CREATE TABLE t1 (
+ pk INT NOT NULL AUTO_INCREMENT,
+ c1_idx CHAR(1) DEFAULT 'y',
+ c2 INT,
+ PRIMARY KEY (pk),
+ INDEX c1_idx (c1_idx)
+) ENGINE=InnoDB;
+--enable_warnings
+INSERT INTO t1 VALUES (1,'y',1), (2,'n',2), (3,'y',3), (4,'n',4);
+--let $query = UPDATE t1 SET c2 = 0 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2
+--let $select = SELECT * FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2
+--source include/explain_non_select.inc
+--let $query = DELETE FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2
+--let $select = SELECT * FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT AUTO_INCREMENT PRIMARY KEY);
+INSERT INTO t1 VALUES (),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),();
+--let $query = UPDATE t1 SET a=a+10 WHERE a > 34
+--let $select = SELECT * FROM t1 WHERE a > 34
+--source include/explain_non_select.inc
+DROP TABLE t1;
+
+CREATE TABLE t1 (c1 INT, c2 INT, c3 INT);
+CREATE TABLE t2 (c1 INT, c2 INT);
+INSERT INTO t1 VALUES (1, 1, 10), (2, 2, 20);
+--let $query = UPDATE t1 LEFT JOIN t2 ON t1.c1 = t2.c1 SET t2.c2 = 10
+--let $select = SELECT * FROM t1 LEFT JOIN t2 ON t1.c1 = t2.c1
+--source include/explain_non_select.inc
+--let $query = UPDATE t1 LEFT JOIN t2 ON t1.c1 = t2.c1 SET t2.c2 = 10 WHERE t1.c3 = 10
+--let $select = SELECT * FROM t1 LEFT JOIN t2 ON t1.c1 = t2.c1 WHERE t1.c3 = 10
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+CREATE TABLE t1(f1 INT, f2 INT);
+CREATE TABLE t2(f3 INT, f4 INT);
+CREATE INDEX IDX ON t2(f3);
+INSERT INTO t1 VALUES(1,0),(2,0);
+INSERT INTO t2 VALUES(1,1),(2,2);
+--let $query = UPDATE t1 SET t1.f2=(SELECT MAX(t2.f4) FROM t2 WHERE t2.f3=t1.f1)
+--let $select = SELECT (SELECT MAX(t2.f4) FROM t2 WHERE t2.f3=t1.f1) FROM t1
+--source include/explain_non_select.inc
+DROP TABLE t1, t2;
+
+
+CREATE TABLE t1(a INT);
+INSERT INTO t1 VALUES (1);
+SET @a = NULL;
+EXPLAIN DELETE FROM t1 WHERE (@a:= a);
+if (`SELECT @a IS NOT NULL`) {
+ die Unexpectedly modified user variable;
+}
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT);
+INSERT INTO t1 VALUES (1), (2), (3);
+--error ER_BAD_FIELD_ERROR
+ DELETE FROM t1 USING t1 WHERE uknown_column = 12345;
+--error ER_BAD_FIELD_ERROR
+EXPLAIN EXTENDED DELETE FROM t1 USING t1 WHERE uknown_column = 12345;
+DROP TABLE t1;
+
+CREATE TABLE t1(f1 INT);
+--error ER_BAD_FIELD_ERROR
+EXPLAIN EXTENDED UPDATE t1 SET f2=1 ORDER BY f2;
+--error ER_BAD_FIELD_ERROR
+UPDATE t1 SET f2=1 ORDER BY f2;
+DROP TABLE t1;
+
+CREATE TABLE t1 ( a INT, KEY( a ) );
+INSERT INTO t1 VALUES (0), (1);
+CREATE VIEW v1 AS SELECT t11.a, t12.a AS b FROM t1 t11, t1 t12;
+SET SESSION sql_safe_updates = 1;
+--error ER_UPDATE_WITHOUT_KEY_IN_SAFE_MODE
+EXPLAIN EXTENDED UPDATE IGNORE v1 SET a = 1;
+--error ER_UPDATE_WITHOUT_KEY_IN_SAFE_MODE
+UPDATE IGNORE v1 SET a = 1;
+SET SESSION sql_safe_updates = DEFAULT;
+DROP TABLE t1;
+DROP VIEW v1;
+
=== modified file 'sql/CMakeLists.txt'
--- a/sql/CMakeLists.txt 2011-02-02 08:30:13 +0000
+++ b/sql/CMakeLists.txt 2011-04-01 13:53:57 +0000
@@ -72,6 +72,7 @@ SET(SQL_SHARED_SOURCES
mf_iocache.cc
my_decimal.cc
net_serv.cc
+ opt_explain.cc
opt_range.cc
opt_sum.cc
parse_file.cc
=== added file 'sql/opt_explain.cc'
--- a/sql/opt_explain.cc 1970-01-01 00:00:00 +0000
+++ b/sql/opt_explain.cc 2011-04-01 13:53:57 +0000
@@ -0,0 +1,1450 @@
+/* Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; version 2 of the License.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ 51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */
+
+#include "opt_explain.h"
+#include "sql_partition.h" // for make_used_partitions_str()
+
+
+/**
+ A base for all Explain_* classes
+
+ This class hierarchy is a successor of the old select_describe() function
+ implementation. It extends old select_describe() functionality to deal with
+ single-table data-modifying commands (UPDATE and DELETE).
+*/
+
+class Explain
+{
+private:
+ List<Item> items; ///< item list to feed select_result::send_data()
+ Item_null *nil; ///< pre-allocated NULL item to fill empty columns in EXPLAIN
+
+protected:
+ /*
+ Next "col_*" fields are intended for the filling by "explain_*()" methods.
+ Then the make_list() method links these Items into "items" list.
+
+ NOTE: NULL value means that Item_null object will be pushed into "items"
+ list instead.
+ */
+ Item_uint *col_id; ///< "id" column: seq. number of SELECT withing the query
+ Item_string *col_select_type; ///< "select_type" column
+ Item_string *col_table_name; ///< "table" to which the row of output refers
+ Item_string *col_partitions; ///< "partitions" column
+ Item_string *col_join_type; ///< "type" column, see join_type_str array
+ Item_string *col_possible_keys; ///< "possible_keys": comma-separated list
+ Item_string *col_key; ///< "key" column: index that is actually decided to use
+ Item_string *col_key_len; ///< "key_length" column: length of the "key" above
+ Item_string *col_ref; ///< "ref":columns/constants which are compared to "key"
+ Item_int *col_rows; ///< "rows": estimated number of examined table rows
+ Item_float *col_filtered; ///< "filtered": % of rows filtered by condition
+ Item_string *col_extra; ///< "extra" column: additional information
+
+ THD *thd; ///< cached THD pointer
+ const CHARSET_INFO *cs; ///< cached pointer to system_charset_info
+ JOIN *join; ///< top-level JOIN (if any) provided by caller
+ SELECT_LEX *select_lex; ///< cached select_lex pointer
+
+ select_result *external_result; ///< result stream (if any) provided by caller
+
+public:
+ explicit Explain(JOIN *join_arg= NULL)
+ : nil(NULL),
+ thd(current_thd),
+ cs(system_charset_info),
+ join(join_arg),
+ select_lex(join ? join->select_lex : &thd->lex->select_lex),
+ external_result(join ? join->result : NULL)
+ {
+ init_columns();
+ }
+ virtual ~Explain() {}
+
+ bool send();
+
+private:
+ void init_columns();
+ bool make_list();
+ bool push(Item *item) { return items.push_back(item ? item : nil); }
+
+protected:
+ bool describe(uint8 mask) { return thd->lex->describe & mask; }
+
+ /**
+ Prepare the self-allocated result object
+
+ For queries with top-level JOIN the caller provides pre-allocated
+ select_send object. Then that JOIN object prepares the select_send
+ object calling result->prepare() in JOIN::prepare(),
+ result->initalize_tables() in JOIN::optimize() and result->prepare2()
+ in JOIN::exe().
+ However witout the presence of the top-level JOIN we have to
+ prepare/initialize select_send object manually.
+ */
+ bool prepare(select_result *result)
+ {
+ DBUG_ASSERT(join == NULL);
+ List<Item> dummy;
+ return result->prepare(dummy, select_lex->master_unit()) ||
+ result->prepare2();
+ }
+
+ virtual bool send_to(select_result *to);
+
+ /*
+ Rest of the methods are overloadable functions those calculate and fill
+ "col_*" fields with Items for further sending as EXPLAIN columns.
+
+ "explain_*" methods return FALSE on success and TRUE on error (usually OOM).
+ */
+ virtual bool explain_id();
+ virtual bool explain_select_type();
+ virtual bool explain_table_name() { return FALSE; }
+ virtual bool explain_partitions() { return FALSE; }
+ virtual bool explain_join_type() { return FALSE; }
+ virtual bool explain_possible_keys() { return FALSE; }
+ /* fill col_key and and col_key_len fields together */
+ virtual bool explain_key_and_len() { return FALSE; }
+ virtual bool explain_ref() { return FALSE; }
+ /* fill col_rows and col_filtered fields together */
+ virtual bool explain_rows_and_filtered() { return FALSE; }
+ virtual bool explain_extra();
+};
+
+
+/**
+ Explain_msg class outputs a trivial EXPLAIN row with "extra" column
+
+ Fromer part of the old select_describe() function.
+ This class is intended for simple cases to produce EXPLAIN output
+ with "No tables used", "No matching records" etc.
+ Optionally it can output number of estimated rows in the "row"
+ column.
+
+ NOTE: this class also produces EXPLAIN rows for inner units (if any).
+*/
+
+class Explain_msg: public Explain
+{
+private:
+ const char *message; ///< cached "message" argument
+ const ha_rows rows; ///< HA_POS_ERROR or cached "rows" argument
+
+public:
+ Explain_msg(JOIN *join_arg, const char *message_arg)
+ : Explain(join_arg), message(message_arg), rows(HA_POS_ERROR)
+ {}
+
+ explicit Explain_msg(const char *message_arg, ha_rows rows_arg= HA_POS_ERROR)
+ : message(message_arg), rows(rows_arg)
+ {}
+
+protected:
+ virtual bool explain_rows_and_filtered();
+ virtual bool explain_extra();
+};
+
+
+/**
+ Explain_union class outputs EXPLAIN row for UNION
+
+ Former part of the old select_describe() function.
+*/
+
+class Explain_union : public Explain
+{
+private:
+ char table_name_buffer[NAME_CHAR_LEN];
+
+public:
+ Explain_union(JOIN *join_arg) : Explain(join_arg)
+ {
+ /* it's a UNION: */
+ DBUG_ASSERT(join_arg->select_lex == join_arg->unit->fake_select_lex);
+ }
+
+protected:
+ virtual bool explain_id();
+ virtual bool explain_table_name();
+ virtual bool explain_join_type();
+ virtual bool explain_extra();
+};
+
+
+
+/**
+ Common base class for Explain_join and Explain_table
+
+ Former part of the old select_describe() function.
+*/
+
+class Explain_table_base : public Explain {
+protected:
+ TABLE *table;
+ key_map usable_keys;
+
+ char buff_possible_keys[512];
+ String str_possible_keys;
+
+public:
+ explicit Explain_table_base(JOIN *join_arg)
+ : Explain(join_arg), table(NULL),
+ str_possible_keys(buff_possible_keys, sizeof(buff_possible_keys), cs)
+ {}
+
+ explicit Explain_table_base(TABLE *table_arg)
+ : table(table_arg),
+ str_possible_keys(buff_possible_keys, sizeof(buff_possible_keys), cs)
+ {}
+
+protected:
+ virtual bool explain_partitions();
+ virtual bool explain_possible_keys();
+};
+
+
+/**
+ Explain_join class produces EXPLAIN output for JOINs
+
+ Former part of the old select_describe() function.
+*/
+
+class Explain_join : public Explain_table_base
+{
+private:
+ const bool need_tmp_table;
+ const bool need_order;
+ const bool distinct;
+
+ uint tabnum;
+ JOIN_TAB *tab;
+ int quick_type;
+ table_map used_tables;
+ uint last_sjm_table;
+
+ char table_name_buffer[NAME_LEN];
+
+ char buff_key[512];
+ String str_key;
+
+ char buff_key_len[512];
+ String str_key_len;
+
+ char buff_ref[512];
+ String str_ref;
+
+ char buff_extra[512];
+ String str_extra;
+
+public:
+ Explain_join(JOIN *join_arg,
+ bool need_tmp_table_arg, bool need_order_arg,
+ bool distinct_arg)
+ : Explain_table_base(join_arg), need_tmp_table(need_tmp_table_arg),
+ need_order(need_order_arg), distinct(distinct_arg),
+ tabnum(0), used_tables(0), last_sjm_table(MAX_TABLES),
+ str_key(buff_key, sizeof(buff_key), cs),
+ str_key_len(buff_key_len, sizeof(buff_key_len), cs),
+ str_ref(buff_ref, sizeof(buff_ref), cs),
+ str_extra(buff_extra, sizeof(buff_extra), cs)
+ {
+ /* it is not UNION: */
+ DBUG_ASSERT(join_arg->select_lex != join_arg->unit->fake_select_lex);
+ }
+
+protected:
+ virtual bool send_to(select_result *to);
+ virtual bool explain_table_name();
+ virtual bool explain_join_type();
+ virtual bool explain_key_and_len();
+ virtual bool explain_ref();
+ virtual bool explain_rows_and_filtered();
+ virtual bool explain_extra();
+};
+
+
+/**
+ Explain_table class produce EXPLAIN output for queries without top-level JOIN
+
+ This class is a simplified version of the Explain_join class. It works in the
+ context of queries which implementation lacks top-level JOIN object (EXPLAIN
+ single-table UPDATE and DELETE).
+*/
+
+class Explain_table: public Explain_table_base
+{
+private:
+ const SQL_SELECT *select; ///< cached "select" argument
+ const uint key; ///< cached "key" number argument
+ const ha_rows limit; ///< HA_POS_ERROR or cached "limit" argument
+ const bool need_sort; ///< cached need_sort argument
+
+ /*
+ Pre-allocated buffers and String wrapper objects for them
+ */
+ char buff_key[512];
+ String str_key;
+ char buff_key_len[512];
+ String str_key_len;
+ char buff_extra[512];
+ String str_extra;
+
+public:
+ Explain_table(TABLE *table_arg, SQL_SELECT *select_arg,
+ uint key_arg, ha_rows limit_arg, bool need_sort_arg)
+ : Explain_table_base(table_arg), select(select_arg), key(key_arg),
+ limit(limit_arg), need_sort(need_sort_arg),
+ str_key(buff_key, sizeof(buff_key), cs),
+ str_key_len(buff_key_len, sizeof(buff_key_len), cs),
+ str_extra(buff_extra, sizeof(buff_extra), cs)
+ {
+ usable_keys= table->keys_in_use_for_query;
+ }
+
+private:
+ virtual bool explain_table_name();
+ virtual bool explain_join_type();
+ virtual bool explain_key_and_len();
+ virtual bool explain_rows_and_filtered();
+ virtual bool explain_extra();
+};
+
+
+static join_type calc_join_type(int quick_type)
+{
+ if ((quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_MERGE) ||
+ (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT) ||
+ (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_UNION))
+ return JT_INDEX_MERGE;
+ else
+ return JT_RANGE;
+}
+
+
+/* Explain class methods ******************************************************/
+
+
+/**
+ Explain class main function
+
+ This method:
+ a) allocates a select_send object (if no one pre-allocated available),
+ b) calculates and sends whole EXPLAIN data.
+
+ @returns
+ @retval FALSE Ok
+ @retval TRUE Error
+*/
+
+bool Explain::send()
+{
+ /* Don't log this into the slow query log */
+ thd->server_status&= ~(SERVER_QUERY_NO_INDEX_USED |
+ SERVER_QUERY_NO_GOOD_INDEX_USED);
+
+ select_result *result;
+ if (external_result == NULL)
+ {
+ /* Create select_result object if the called doesn't provide one: */
+ result= new select_send;
+ if (!(result= new select_send))
+ return TRUE;
+ if (thd->send_explain_fields(result) || prepare(result))
+ {
+ delete result;
+ return TRUE;
+ }
+ }
+ else
+ {
+ result= external_result;
+ external_result->reset_offset_limit_cnt();
+ }
+
+ if (!(nil= new Item_null))
+ return TRUE;
+ bool ret= send_to(result);
+
+ if (ret && join)
+ join->error= 1;
+
+ for (SELECT_LEX_UNIT *unit= select_lex->first_inner_unit();
+ unit && !ret;
+ unit= unit->next_unit())
+ ret= mysql_explain_union(thd, unit, result);
+
+ if (external_result == NULL)
+ {
+ if (ret)
+ result->abort_result_set();
+ else
+ result->send_eof();
+ delete result;
+ }
+ return ret;
+}
+
+
+/**
+ Reset all "col_*" fields
+*/
+
+void Explain::init_columns()
+{
+ col_id= NULL;
+ col_select_type= NULL;
+ col_table_name= NULL;
+ col_partitions= NULL;
+ col_join_type= NULL;
+ col_possible_keys= NULL;
+ col_key= NULL;
+ col_key_len= NULL;
+ col_ref= NULL;
+ col_rows= NULL;
+ col_filtered= NULL;
+ col_extra= NULL;
+}
+
+
+/**
+ Calculate EXPLAIN column values and link them into "items" list
+
+ @returns
+ @retval FALSE Ok
+ @retval TRUE Error
+*/
+
+bool Explain::make_list()
+{
+ if (explain_id() ||
+ explain_select_type() ||
+ explain_table_name() ||
+ explain_partitions() ||
+ explain_join_type() ||
+ explain_possible_keys() ||
+ explain_key_and_len() ||
+ explain_ref() ||
+ explain_rows_and_filtered() ||
+ explain_extra())
+ return TRUE;
+
+ /*
+ NOTE: the number/types of items pushed into item_list must be in sync with
+ EXPLAIN column types as they're "defined" in THD::send_explain_fields()
+ */
+ return push(col_id) ||
+ push(col_select_type) ||
+ push(col_table_name) ||
+ (describe(DESCRIBE_PARTITIONS) && push(col_partitions)) ||
+ push(col_join_type) ||
+ push(col_possible_keys) ||
+ push(col_key) ||
+ push(col_key_len) ||
+ push(col_ref) ||
+ push(col_rows) ||
+ (describe(DESCRIBE_EXTENDED) && push(col_filtered)) ||
+ push(col_extra);
+}
+
+
+/**
+ Make "items" list and send it to select_result output stream
+
+ This method is virtual since the base implementation is intended for sending
+ the "items" list once, but the overloaded Explain_join implementation sends
+ it many times (once for each JOIN::join_tab[] element).
+
+ @returns
+ @retval FALSE Ok
+ @retval TRUE Error
+*/
+
+bool Explain::send_to(select_result *to)
+{
+ bool ret= make_list() || to->send_data(items);
+ items.empty();
+ init_columns();
+ return ret;
+}
+
+
+bool Explain::explain_id()
+{
+ col_id= new Item_uint(select_lex->select_number);
+ return col_id == NULL;
+}
+
+
+bool Explain::explain_select_type()
+{
+ if (select_lex->type)
+ col_select_type= new Item_string(select_lex->type,
+ strlen(select_lex->type), cs);
+ else if (select_lex->first_inner_unit() || select_lex->next_select())
+ col_select_type= new Item_string(STRING_WITH_LEN("PRIMARY"), cs);
+ else
+ col_select_type= new Item_string(STRING_WITH_LEN("SIMPLE"), cs);
+ return col_select_type == NULL;
+}
+
+
+bool Explain::explain_extra()
+{
+ col_extra= new Item_string("", 0, cs);
+ return col_extra == NULL;
+}
+
+
+/* Explain_msg class methods **************************************************/
+
+
+bool Explain_msg::explain_rows_and_filtered()
+{
+ if (rows == HA_POS_ERROR)
+ return FALSE;
+ col_rows= new Item_int(rows, MY_INT64_NUM_DECIMAL_DIGITS);
+ return col_rows == NULL;
+}
+
+
+bool Explain_msg::explain_extra()
+{
+ col_extra= new Item_string(message, strlen(message), cs);
+ return col_extra == NULL;
+}
+
+
+/* Explain_union class methods ************************************************/
+
+
+bool Explain_union::explain_id()
+{
+ col_id= NULL;
+ return FALSE;
+}
+
+
+bool Explain_union::explain_table_name()
+{
+ SELECT_LEX *last_select= join->unit->first_select()->last_select();
+ // # characters needed to print select_number of last select
+ int last_length= (int)log10((double)last_select->select_number)+1;
+
+ SELECT_LEX *sl= join->unit->first_select();
+ uint len= 6, lastop= 0;
+ memcpy(table_name_buffer, STRING_WITH_LEN("<union"));
+ /*
+ - len + lastop: current position in table_name_buffer
+ - 6 + last_length: the number of characters needed to print
+ '...,'<last_select->select_number>'>\0'
+ */
+ for (;
+ sl && len + lastop + 6 + last_length < NAME_CHAR_LEN;
+ sl= sl->next_select())
+ {
+ len+= lastop;
+ lastop= my_snprintf(table_name_buffer + len, NAME_CHAR_LEN - len,
+ "%u,", sl->select_number);
+ }
+ if (sl || len + lastop >= NAME_CHAR_LEN)
+ {
+ memcpy(table_name_buffer + len, STRING_WITH_LEN("...,"));
+ len+= 4;
+ lastop= my_snprintf(table_name_buffer + len, NAME_CHAR_LEN - len,
+ "%u,", last_select->select_number);
+ }
+ len+= lastop;
+ table_name_buffer[len - 1]= '>'; // change ',' to '>'
+
+ col_table_name= new Item_string(table_name_buffer, len, cs);
+
+ return col_table_name == NULL;
+}
+
+
+bool Explain_union::explain_join_type()
+{
+ col_join_type= new Item_string(join_type_str[JT_ALL],
+ strlen(join_type_str[JT_ALL]), cs);
+ return col_join_type == NULL;
+}
+
+
+bool Explain_union::explain_extra()
+{
+ /*
+ Moved from select_describe():
+
+ here we assume that the query will return at least two rows, so we
+ show "filesort" in EXPLAIN. Of course, sometimes we'll be wrong
+ and no filesort will be actually done, but executing all selects in
+ the UNION to provide precise EXPLAIN information will hardly be
+ appreciated :)
+ */
+ if (join->unit->global_parameters->order_list.first)
+ {
+ col_extra= new Item_string(STRING_WITH_LEN("Using filesort"), cs);
+ return col_extra == NULL;
+ }
+ return Explain::explain_extra();
+}
+
+
+/* Explain_table_base class methods *******************************************/
+
+
+bool Explain_table_base::explain_partitions()
+{
+#ifdef WITH_PARTITION_STORAGE_ENGINE
+ if (!table->derived_select_number && table->part_info)
+ {
+ col_partitions= new Item_string(cs);
+ if (col_partitions == NULL)
+ return TRUE;
+ make_used_partitions_str(table->part_info, &col_partitions->str_value);
+ }
+#endif
+ return FALSE;
+}
+
+
+bool Explain_table_base::explain_possible_keys()
+{
+ if (usable_keys.is_clear_all())
+ return FALSE;
+
+ str_possible_keys.length(0);
+
+ for (uint j=0 ; j < table->s->keys ; j++)
+ {
+ if (usable_keys.is_set(j))
+ {
+ if (str_possible_keys.length())
+ str_possible_keys.append(',');
+ str_possible_keys.append(table->key_info[j].name,
+ strlen(table->key_info[j].name), cs);
+ }
+ }
+ if (str_possible_keys.length())
+ {
+ col_possible_keys= new Item_string(str_possible_keys.ptr(),
+ str_possible_keys.length(), cs);
+ return col_possible_keys == NULL;
+ }
+ return FALSE;
+}
+
+
+/* Explain_join class methods *************************************************/
+
+
+bool Explain_join::send_to(select_result *to)
+{
+ for (; tabnum < join->tables; tabnum++)
+ {
+ tab= join->join_tab + tabnum;
+ table= tab->table;
+ usable_keys= tab->keys;
+ quick_type= -1;
+
+ if (tab->type == JT_ALL && tab->select && tab->select->quick)
+ {
+ quick_type= tab->select->quick->get_type();
+ tab->type= calc_join_type(quick_type);
+ }
+
+ if (Explain_table_base::send_to(external_result))
+ return TRUE;
+
+ used_tables|= table->map;
+ }
+ return FALSE;
+}
+
+
+bool Explain_join::explain_table_name()
+{
+ if (table->derived_select_number)
+ {
+ /* Derived table name generation */
+ int len= my_snprintf(table_name_buffer, sizeof(table_name_buffer) - 1,
+ "<derived%u>", table->derived_select_number);
+ col_table_name= new Item_string(table_name_buffer, len, cs);
+ }
+ else
+ {
+ TABLE_LIST *real_table= table->pos_in_table_list;
+ col_table_name= new Item_string(real_table->alias,
+ strlen(real_table->alias), cs);
+ }
+ return col_table_name == NULL;
+}
+
+
+bool Explain_join::explain_join_type()
+{
+ col_join_type= new Item_string(join_type_str[tab->type],
+ strlen(join_type_str[tab->type]), cs);
+ return col_join_type == NULL;
+}
+
+
+bool Explain_join::explain_key_and_len()
+{
+ str_key.length(0);
+ str_key_len.length(0);
+
+ if (tab->ref.key_parts)
+ {
+ KEY *key_info= table->key_info + tab->ref.key;
+ uint length;
+ col_key= new Item_string(key_info->name, strlen(key_info->name), cs);
+ length= longlong2str(tab->ref.key_length, buff_key_len, 10) - buff_key_len;
+ col_key_len= new Item_string(buff_key_len, length, cs);
+ return col_key == NULL || col_key_len == NULL;
+ }
+ else if (tab->type == JT_NEXT)
+ {
+ KEY *key_info= table->key_info + tab->index;
+ uint length;
+ col_key= new Item_string(key_info->name, strlen(key_info->name), cs);
+ length= longlong2str(key_info->key_length, buff_key_len, 10) -
+ buff_key_len;
+ col_key_len= new Item_string(buff_key_len, length, cs);
+ return col_key == NULL || col_key_len == NULL;
+ }
+ else if (tab->select && tab->select->quick)
+ {
+ tab->select->quick->add_keys_and_lengths(&str_key, &str_key_len);
+ col_key= new Item_string(str_key.ptr(), str_key.length(), cs);
+ col_key_len= new Item_string(str_key_len.ptr(), str_key_len.length(), cs);
+ return col_key == NULL || col_key_len == NULL;
+ }
+ else
+ {
+ TABLE_LIST *table_list= tab->table->pos_in_table_list;
+ if (table_list->schema_table &&
+ table_list->schema_table->i_s_requested_object & OPTIMIZE_I_S_TABLE)
+ {
+ const char *f_name;
+ int f_idx;
+ if (table_list->has_db_lookup_value)
+ {
+ f_idx= table_list->schema_table->idx_field1;
+ f_name= table_list->schema_table->fields_info[f_idx].field_name;
+ str_key.append(f_name, strlen(f_name), cs);
+ }
+ if (table_list->has_table_lookup_value)
+ {
+ if (table_list->has_db_lookup_value)
+ str_key.append(',');
+ f_idx= table_list->schema_table->idx_field2;
+ f_name= table_list->schema_table->fields_info[f_idx].field_name;
+ str_key.append(f_name, strlen(f_name), cs);
+ }
+ if (str_key.length())
+ {
+ col_key= new Item_string(str_key.ptr(), str_key.length(), cs);
+ return col_key == NULL;
+ }
+ }
+ }
+ return FALSE;
+}
+
+
+bool Explain_join::explain_ref()
+{
+ str_ref.length(0);
+
+ if (tab->ref.key_parts)
+ {
+ for (store_key **ref= tab->ref.key_copy; *ref; ref++)
+ {
+ if (str_ref.length())
+ str_ref.append(',');
+ str_ref.append((*ref)->name(), strlen((*ref)->name()), cs);
+ }
+ col_ref= new Item_string(str_ref.ptr(), str_ref.length(), cs);
+ return col_ref == NULL;
+ }
+ return FALSE;
+}
+
+
+bool Explain_join::explain_rows_and_filtered()
+{
+ if (tab->table->pos_in_table_list->schema_table)
+ return FALSE;
+
+ double examined_rows;
+ if (tab->select && tab->select->quick)
+ examined_rows= rows2double(tab->select->quick->records);
+ else if (tab->type == JT_NEXT || tab->type == JT_ALL)
+ {
+ if (tab->limit)
+ examined_rows= rows2double(tab->limit);
+ else
+ {
+ tab->table->file->info(HA_STATUS_VARIABLE);
+ examined_rows= rows2double(tab->table->file->stats.records);
+ }
+ }
+ else
+ examined_rows= join->best_positions[tabnum].records_read;
+
+ col_rows= new Item_int((longlong) (ulonglong) examined_rows,
+ MY_INT64_NUM_DECIMAL_DIGITS);
+ if (col_rows == NULL)
+ return TRUE;
+
+ /* Add "filtered" field */
+ if (describe(DESCRIBE_EXTENDED))
+ {
+ float f= 0.0;
+ if (examined_rows)
+ f= (float) (100.0 * join->best_positions[tabnum].records_read /
+ examined_rows);
+ col_filtered= new Item_float(f, 2);
+ if (col_filtered == NULL)
+ return TRUE;
+ }
+ return FALSE;
+}
+
+
+bool Explain_join::explain_extra()
+{
+ str_extra.length(0);
+
+ my_bool key_read=table->key_read;
+ if ((tab->type == JT_NEXT || tab->type == JT_CONST) &&
+ table->covering_keys.is_set(tab->index))
+ key_read=1;
+ if (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT &&
+ !((QUICK_ROR_INTERSECT_SELECT*)tab->select->quick)->need_to_fetch_row)
+ key_read=1;
+
+ if (tab->info)
+ col_extra= new Item_string(tab->info,strlen(tab->info), cs);
+ else if (tab->packed_info & TAB_INFO_HAVE_VALUE)
+ {
+ if (tab->packed_info & TAB_INFO_USING_INDEX)
+ str_extra.append(STRING_WITH_LEN("; Using index"));
+ if (tab->packed_info & TAB_INFO_USING_WHERE)
+ str_extra.append(STRING_WITH_LEN("; Using where"));
+ if (tab->packed_info & TAB_INFO_FULL_SCAN_ON_NULL)
+ str_extra.append(STRING_WITH_LEN("; Full scan on NULL key"));
+ /* Skip initial "; "*/
+ const char *str= str_extra.ptr();
+ uint32 len= str_extra.length();
+ if (len)
+ {
+ str += 2;
+ len -= 2;
+ }
+ col_extra= new Item_string(str, len, cs);
+ }
+ else
+ {
+ uint keyno= MAX_KEY;
+ if (tab->ref.key_parts)
+ keyno= tab->ref.key;
+ else if (tab->select && tab->select->quick)
+ keyno = tab->select->quick->index;
+
+ if ((keyno != MAX_KEY && keyno == table->file->pushed_idx_cond_keyno &&
+ table->file->pushed_idx_cond) || tab->cache_idx_cond)
+ str_extra.append(STRING_WITH_LEN("; Using index condition"));
+
+ if (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_UNION ||
+ quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT ||
+ quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_MERGE)
+ {
+ str_extra.append(STRING_WITH_LEN("; Using "));
+ tab->select->quick->add_info_string(&str_extra);
+ }
+ if (tab->select)
+ {
+ if (tab->use_quick == QS_DYNAMIC_RANGE)
+ {
+ /* 4 bits per 1 hex digit + terminating '\0' */
+ char buf[MAX_KEY / 4 + 1];
+ str_extra.append(STRING_WITH_LEN("; Range checked for each "
+ "record (index map: 0x"));
+ str_extra.append(tab->keys.print(buf));
+ str_extra.append(')');
+ }
+ else if (tab->select->cond)
+ {
+ const Item *pushed_cond= tab->table->file->pushed_cond;
+
+ if (thd->optimizer_switch_flag(OPTIMIZER_SWITCH_ENGINE_CONDITION_PUSHDOWN) &&
+ pushed_cond)
+ {
+ str_extra.append(STRING_WITH_LEN("; Using where with pushed "
+ "condition"));
+ if (describe(DESCRIBE_EXTENDED))
+ {
+ str_extra.append(STRING_WITH_LEN(": "));
+ ((Item *)pushed_cond)->print(&str_extra, QT_ORDINARY);
+ }
+ }
+ else
+ str_extra.append(STRING_WITH_LEN("; Using where"));
+ }
+ }
+ TABLE_LIST *table_list= tab->table->pos_in_table_list;
+ if (table_list->schema_table &&
+ table_list->schema_table->i_s_requested_object & OPTIMIZE_I_S_TABLE)
+ {
+ if (!table_list->table_open_method)
+ str_extra.append(STRING_WITH_LEN("; Skip_open_table"));
+ else if (table_list->table_open_method == OPEN_FRM_ONLY)
+ str_extra.append(STRING_WITH_LEN("; Open_frm_only"));
+ else
+ str_extra.append(STRING_WITH_LEN("; Open_full_table"));
+ if (table_list->has_db_lookup_value &&
+ table_list->has_table_lookup_value)
+ str_extra.append(STRING_WITH_LEN("; Scanned 0 databases"));
+ else if (table_list->has_db_lookup_value ||
+ table_list->has_table_lookup_value)
+ str_extra.append(STRING_WITH_LEN("; Scanned 1 database"));
+ else
+ str_extra.append(STRING_WITH_LEN("; Scanned all databases"));
+ }
+ if (key_read)
+ {
+ if (quick_type == QUICK_SELECT_I::QS_TYPE_GROUP_MIN_MAX)
+ {
+ QUICK_GROUP_MIN_MAX_SELECT *qgs=
+ (QUICK_GROUP_MIN_MAX_SELECT *) tab->select->quick;
+ str_extra.append(STRING_WITH_LEN("; Using index for group-by"));
+ qgs->append_loose_scan_type(&str_extra);
+ }
+ else
+ str_extra.append(STRING_WITH_LEN("; Using index"));
+ }
+ if (table->reginfo.not_exists_optimize)
+ str_extra.append(STRING_WITH_LEN("; Not exists"));
+
+ if (quick_type == QUICK_SELECT_I::QS_TYPE_RANGE &&
+ !(((QUICK_RANGE_SELECT*)(tab->select->quick))->mrr_flags &
+ (HA_MRR_USE_DEFAULT_IMPL | HA_MRR_SORTED)))
+ {
+ /*
+ During normal execution of a query, multi_range_read_init() is
+ called to initialize MRR. If HA_MRR_SORTED is set at this point,
+ multi_range_read_init() for any native MRR implementation will
+ revert to default MRR because they cannot produce sorted output
+ currently.
+ Calling multi_range_read_init() can potentially be costly, so it
+ is not done when executing an EXPLAIN. We therefore make the
+ assumption that HA_MRR_SORTED means no MRR. If some MRR native
+ implementation will support sorted output in the future, a
+ function "bool mrr_supports_sorted()" should be added in the
+ handler.
+ */
+ str_extra.append(STRING_WITH_LEN("; Using MRR"));
+ }
+ if (tabnum == 0 && need_tmp_table)
+ str_extra.append(STRING_WITH_LEN("; Using temporary"));
+
+ if (tabnum == 0 && need_order)
+ str_extra.append(STRING_WITH_LEN("; Using filesort"));
+
+ if (distinct && test_all_bits(used_tables,thd->used_tables))
+ str_extra.append(STRING_WITH_LEN("; Distinct"));
+
+ if (tab->loosescan_match_tab)
+ {
+ str_extra.append(STRING_WITH_LEN("; LooseScan"));
+ }
+
+ if (tab->flush_weedout_table)
+ str_extra.append(STRING_WITH_LEN("; Start temporary"));
+ if (tab->check_weed_out_table)
+ str_extra.append(STRING_WITH_LEN("; End temporary"));
+ else if (tab->do_firstmatch)
+ {
+ if (tab->do_firstmatch == join->join_tab - 1)
+ str_extra.append(STRING_WITH_LEN("; FirstMatch"));
+ else
+ {
+ str_extra.append(STRING_WITH_LEN("; FirstMatch("));
+ TABLE *prev_table=tab->do_firstmatch->table;
+ if (prev_table->derived_select_number)
+ {
+ char namebuf[NAME_LEN];
+ /* Derived table name generation */
+ int len= my_snprintf(namebuf, sizeof(namebuf)-1,
+ "<derived%u>",
+ prev_table->derived_select_number);
+ str_extra.append(namebuf, len);
+ }
+ else
+ str_extra.append(prev_table->pos_in_table_list->alias);
+ str_extra.append(STRING_WITH_LEN(")"));
+ }
+ }
+ uint sj_strategy= join->best_positions[tabnum].sj_strategy;
+ if (sj_is_materialize_strategy(sj_strategy))
+ {
+ if (join->best_positions[tabnum].n_sj_tables == 1)
+ str_extra.append(STRING_WITH_LEN("; Materialize"));
+ else
+ {
+ last_sjm_table= tabnum + join->best_positions[tabnum].n_sj_tables - 1;
+ str_extra.append(STRING_WITH_LEN("; Start materialize"));
+ }
+ if (sj_strategy == SJ_OPT_MATERIALIZE_SCAN)
+ str_extra.append(STRING_WITH_LEN("; Scan"));
+ }
+ else if (last_sjm_table == tabnum)
+ {
+ str_extra.append(STRING_WITH_LEN("; End materialize"));
+ }
+
+ for (uint part= 0; part < tab->ref.key_parts; part++)
+ {
+ if (tab->ref.cond_guards[part])
+ {
+ str_extra.append(STRING_WITH_LEN("; Full scan on NULL key"));
+ break;
+ }
+ }
+
+ if (tabnum > 0 && tab[-1].next_select == sub_select_cache)
+ {
+ str_extra.append(STRING_WITH_LEN("; Using join buffer ("));
+ if ((tab->use_join_cache & JOIN_CACHE::ALG_BNL))
+ str_extra.append(STRING_WITH_LEN("BNL"));
+ else if ((tab->use_join_cache & JOIN_CACHE::ALG_BKA))
+ str_extra.append(STRING_WITH_LEN("BKA"));
+ else if ((tab->use_join_cache & JOIN_CACHE::ALG_BKA_UNIQUE))
+ str_extra.append(STRING_WITH_LEN("BKA_UNIQUE"));
+ else
+ DBUG_ASSERT(0);
+ if (tab->use_join_cache & JOIN_CACHE::NON_INCREMENTAL_BUFFER)
+ str_extra.append(STRING_WITH_LEN(", regular buffers)"));
+ else
+ str_extra.append(STRING_WITH_LEN(", incremental buffers)"));
+ }
+
+ /* Skip initial "; "*/
+ const char *str= str_extra.ptr();
+ uint32 len= str_extra.length();
+ if (len)
+ {
+ str += 2;
+ len -= 2;
+ }
+ col_extra= new Item_string(str, len, cs);
+ }
+ return col_extra == NULL;
+}
+
+
+/* Explain_table class methods ************************************************/
+
+
+bool Explain_table::explain_table_name()
+{
+ col_table_name= new Item_string(table->alias, strlen(table->alias), cs);
+ return col_table_name == NULL;
+}
+
+
+bool Explain_table::explain_join_type()
+{
+ join_type jt;
+ if (select && select->quick)
+ jt= calc_join_type(select->quick->get_type());
+ else
+ jt= JT_ALL;
+
+ col_join_type= new Item_string(join_type_str[jt],
+ strlen(join_type_str[jt]), cs);
+ return col_join_type == NULL;
+}
+
+
+bool Explain_table::explain_key_and_len()
+{
+ str_key.length(0);
+ str_key_len.length(0);
+
+ if (key != MAX_KEY)
+ {
+ KEY *key_info= table->key_info + key;
+ col_key= new Item_string(key_info->name, strlen(key_info->name), cs);
+ int length= longlong2str(key_info->key_length, buff_key_len, 10) -
+ buff_key_len;
+ col_key_len= new Item_string(buff_key_len, length, cs);
+ return col_key == NULL || col_key_len == NULL;
+ }
+ else if (select && select->quick)
+ {
+ select->quick->add_keys_and_lengths(&str_key, &str_key_len);
+ col_key= new Item_string(str_key.ptr(), str_key.length(), cs);
+ col_key_len= new Item_string(str_key_len.ptr(), str_key_len.length(), cs);
+ return col_key == NULL || col_key_len == NULL;
+ }
+ return FALSE;
+}
+
+
+bool Explain_table::explain_rows_and_filtered()
+{
+ double examined_rows;
+ if (select && select->quick)
+ examined_rows= rows2double(select->quick->records);
+ else if (!select && !need_sort && limit != HA_POS_ERROR)
+ examined_rows= rows2double(limit);
+ else
+ {
+ table->file->info(HA_STATUS_VARIABLE);
+ examined_rows= rows2double(table->file->stats.records);
+ }
+ col_rows= new Item_int((longlong) (ulonglong) examined_rows,
+ MY_INT64_NUM_DECIMAL_DIGITS);
+ if (col_rows == NULL)
+ return TRUE;
+
+ if (describe(DESCRIBE_EXTENDED))
+ {
+ col_filtered= new Item_float(100.0, 2);
+ if (col_filtered == NULL)
+ return TRUE;
+ }
+ return FALSE;
+}
+
+
+bool Explain_table::explain_extra()
+{
+ str_extra.length(0);
+
+ uint keyno= (select && select->quick) ? select->quick->index : key;
+
+ if (keyno != MAX_KEY && keyno == table->file->pushed_idx_cond_keyno &&
+ table->file->pushed_idx_cond)
+ str_extra.append(STRING_WITH_LEN("; Using index condition"));
+
+ int quick_type= (select && select->quick) ? select->quick->get_type() : -1;
+
+ switch (quick_type) {
+ case QUICK_SELECT_I::QS_TYPE_ROR_UNION:
+ case QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT:
+ case QUICK_SELECT_I::QS_TYPE_INDEX_MERGE:
+ str_extra.append(STRING_WITH_LEN("; Using "));
+ select->quick->add_info_string(&str_extra);
+ break;
+ default: ;
+ }
+
+ if (select && select->cond)
+ {
+ const Item *pushed_cond= table->file->pushed_cond;
+
+ if (thd->optimizer_switch_flag(OPTIMIZER_SWITCH_ENGINE_CONDITION_PUSHDOWN) &&
+ pushed_cond)
+ {
+ str_extra.append(STRING_WITH_LEN("; Using where with pushed "
+ "condition"));
+ if (describe(DESCRIBE_EXTENDED))
+ {
+ str_extra.append(STRING_WITH_LEN(": "));
+ ((Item *)pushed_cond)->print(&str_extra, QT_ORDINARY);
+ }
+ }
+ else
+ str_extra.append(STRING_WITH_LEN("; Using where"));
+ }
+
+ if (table->reginfo.not_exists_optimize)
+ str_extra.append(STRING_WITH_LEN("; Not exists"));
+
+ if (quick_type == QUICK_SELECT_I::QS_TYPE_RANGE &&
+ !(((QUICK_RANGE_SELECT*)(select->quick))->mrr_flags &
+ (HA_MRR_USE_DEFAULT_IMPL | HA_MRR_SORTED)))
+ {
+ /*
+ During normal execution of a query, multi_range_read_init() is
+ called to initialize MRR. If HA_MRR_SORTED is set at this point,
+ multi_range_read_init() for any native MRR implementation will
+ revert to default MRR because they cannot produce sorted output
+ currently.
+ Calling multi_range_read_init() can potentially be costly, so it
+ is not done when executing an EXPLAIN. We therefore make the
+ assumption that HA_MRR_SORTED means no MRR. If some MRR native
+ implementation will support sorted output in the future, a
+ function "bool mrr_supports_sorted()" should be added in the
+ handler.
+ */
+ str_extra.append(STRING_WITH_LEN("; Using MRR"));
+ }
+ if (need_sort)
+ str_extra.append(STRING_WITH_LEN("; Using filesort"));
+
+ /* Skip initial "; "*/
+ const char *str= str_extra.ptr();
+ uint32 len= str_extra.length();
+ if (len)
+ {
+ str += 2;
+ len -= 2;
+ }
+ col_extra= new Item_string(str, len, cs);
+ return col_extra == NULL;
+}
+
+
+/**
+ EXPLAIN functionality for insert_select, multi_update and multi_delete
+
+ This class objects substitute insert_select, multi_update and multi_delete
+ data interceptor objects to implement EXPLAIN for INSERT, REPLACE and
+ multi-table UPDATE and DELETE queries.
+ explain_send class object initializes tables like insert_select, multi_update
+ or multi_delete data interceptor do, but it suppress table data modification
+ by the underlying interceptor object.
+ Thus, we can use explain_send object in the context of EXPLAIN INSERT/
+ REPLACE/UPDATE/DELETE query like we use select_send in the context of
+ EXPLAIN SELECT command:
+ 1) in presence of lex->describe flag we pass explain_send object to the
+ mysql_select() function,
+ 2) it call prepare(), prepare2() and initialize_tables() methods to
+ mark modified tables etc.
+
+*/
+
+class explain_send : public select_send {
+protected:
+ /**
+ Bits for result_state bitmap
+
+ As far as we use explain_send object in a place of select_send, explain_send
+ have to pass multiple invocation of its prepare(), prepare2() and
+ initialize_tables() methods, since JOIN::exec() of subqueries runs
+ these methods of select_send multiple times by design.
+ insert_select, multi_update and multi_delete class methods are not intended
+ for multiple invocations, so result_state bitmap guards data interceptor
+ object from method re-invocation.
+ */
+ enum result_state_enum {
+ SELECT_RESULT_PREPARED = 0x01, // 1st bit set: prepare() is complete
+ SELECT_RESULT_PREPARED2 = 0x02, // 2nd bit set: prepare2() is complete
+ SELECT_RESULT_INITIALIZED = 0x04 // 3rd bit set: initialize_tables() done
+ };
+ int result_state; ///< bitmap of result_state_enum bits
+
+ /**
+ Pointer to underlying insert_select, multi_update or multi_delete object
+ */
+ select_result_interceptor *interceptor;
+
+public:
+ explain_send(select_result_interceptor *interceptor_arg)
+ : result_state(0), interceptor(interceptor_arg)
+ {}
+
+protected:
+ virtual int prepare(List<Item> &list, SELECT_LEX_UNIT *u)
+ {
+ if (result_state & SELECT_RESULT_PREPARED)
+ return FALSE;
+ else
+ result_state|= SELECT_RESULT_PREPARED;
+ return select_send::prepare(list, u) || interceptor->prepare(list, u);
+ }
+
+ virtual int prepare2(void)
+ {
+ if (result_state & SELECT_RESULT_PREPARED2)
+ return FALSE;
+ else
+ result_state|= SELECT_RESULT_PREPARED2;
+ return select_send::prepare2() || interceptor->prepare2();
+ }
+
+ virtual bool initialize_tables(JOIN *join)
+ {
+ if (result_state & SELECT_RESULT_INITIALIZED)
+ return FALSE;
+ else
+ result_state|= SELECT_RESULT_INITIALIZED;
+ return select_send::initialize_tables(join) ||
+ interceptor->initialize_tables(join);
+ }
+
+ virtual void cleanup()
+ {
+ select_send::cleanup();
+ interceptor->cleanup();
+ }
+};
+
+
+/******************************************************************************
+ External function implementations
+******************************************************************************/
+
+
+/**
+ Send a messages as an "extra" column value
+
+ This function forms the 1st row of the QEP output with a simple text message.
+ This is useful to explain such trivial cases as "No tables used" etc.
+
+ NOTE: Also this function explains the rest of QEP (subqueries or joined
+ tables if any).
+
+ @param message text message for the "extra" column.
+ @param rows HA_POS_ERROR or a value for the "rows" column.
+
+ @returns
+ @retval FALSE OK
+ @retval TRUE Error
+*/
+
+bool msg_describe(JOIN *join, const char *message)
+{
+ return Explain_msg(join, message).send();
+}
+
+
+/**
+ Send a messages as an "extra" column value
+
+ This function forms the 1st row of the QEP output with a simple text message.
+ This is useful to explain such trivial cases as "No tables used" etc.
+
+ NOTE: Also this function explains the rest of QEP (subqueries if any).
+
+ @param message text message for the "extra" column.
+ @param rows HA_POS_ERROR or a value for the "rows" column.
+
+ @returns
+ @retval FALSE OK
+ @retval TRUE Error
+*/
+
+bool msg_describe(const char *message, ha_rows rows)
+{
+ return Explain_msg(message, rows).send();
+}
+
+
+/**
+ EXPLAIN handling for single-table UPDATE and DELETE queries
+
+ Send to the client a QEP data set for single-table EXPLAIN UPDATE/DELETE
+ queries. As far as single-table UPDATE/DELETE are implemented without
+ the regular JOIN tree, we can't reuse mysql_explain_union() directly,
+ thus we deal with this single table in a special way and then call
+ mysql_explain_union() for subqueries (if any).
+
+ @param table TABLE object to update/delete rows in the UPDATE/DELETE
+ query.
+ @param select SQL_SELECT object that represents quick access methods/
+ WHERE clause.
+ @param key MAX_KEY or and index number of the key that was chosen to
+ access table data.
+ @param limit HA_POS_ERROR or LIMIT value.
+ @param need_sort TRUE if it requires filesort() -- "Using filesort"
+ string in the "extra" column.
+
+ @returns
+ @retval FALSE OK
+ @retval TRUE Error
+*/
+
+bool table_describe(TABLE *table, SQL_SELECT *select, uint key, ha_rows limit,
+ bool need_sort)
+{
+ return Explain_table(table, select, key, limit, need_sort).send();
+}
+
+
+/**
+ EXPLAIN handling for EXPLAIN SELECT queries
+
+ Send a description about what how the select will be done to the client
+
+ @param join JOIN
+ @param need_tmp_table TRUE if it requires a temporary table --
+ "Using temporary" string in the "extra" column.
+ @param need_order TRUE if it requires filesort() -- "Using filesort"
+ string in the "extra" column.
+ @param distinct TRUE if there is the DISTINCT clause (not optimized
+ out) -- "Distinct" string in the "extra" column.
+
+ @returns
+ @retval FALSE OK
+ @retval TRUE Error
+*/
+
+bool select_describe(JOIN *join, bool need_tmp_table, bool need_order,
+ bool distinct)
+{
+ DBUG_ENTER("select_describe");
+ DBUG_PRINT("info", ("Select 0x%lx, type %s",
+ (ulong)join->select_lex, join->select_lex->type));
+ if (join->select_lex == join->unit->fake_select_lex)
+ DBUG_RETURN(Explain_union(join).send());
+ else
+ DBUG_RETURN(Explain_join(join, need_tmp_table, need_order, distinct).send());
+}
+
+
+/**
+ EXPLAIN handling for INSERT, REPLACE and multi-table UPDATE/DELETE queries
+
+ Send to the client a QEP data set for data-modifying commands those have a
+ regular JOIN tree (INSERT...SELECT, REPLACE...SELECT and multi-table
+ UPDATE and DELETE queries) like mysql_select() does for SELECT queries in
+ the "describe" mode.
+
+ NOTE: See table_describe() for single-table UPDATE/DELETE EXPLAIN handling.
+
+ NOTE: Unlike the mysql_select() function, explain_data_modification()
+ calls abort_result_set() itself in the case of failure (OOM etc.)
+ since explain_data_modification() uses internally created select_result
+ stream.
+
+ @param result pointer to select_insert, multi_delete or multi_update object:
+ the function uses it to call result->prepare(),
+ result->prepare2() and result->initialize_tables() only but
+ not to modify table data or to send a result to client.
+ @returns
+ @retval FALSE OK
+ @retval TRUE Error
+*/
+
+bool explain_data_modification(select_result_interceptor *result)
+{
+ THD *thd= current_thd;
+ explain_send explain(result);
+ bool res= thd->send_explain_fields(&explain) ||
+ mysql_explain_union(thd, &thd->lex->unit, &explain) ||
+ thd->is_error();
+ if (res)
+ explain.abort_result_set();
+ else
+ explain.send_eof();
+ return res;
+}
+
=== added file 'sql/opt_explain.h'
--- a/sql/opt_explain.h 1970-01-01 00:00:00 +0000
+++ b/sql/opt_explain.h 2011-04-01 13:53:57 +0000
@@ -0,0 +1,30 @@
+/* Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; version 2 of the License.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ 51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */
+
+
+#ifndef SQL_EXPLAIN_INCLUDED
+#define SQL_EXPLAIN_INCLUDED
+
+#include "sql_select.h"
+
+bool msg_describe(JOIN *join, const char *message);
+bool msg_describe(const char *message, ha_rows rows= HA_POS_ERROR);
+bool table_describe(TABLE *table, SQL_SELECT *select, uint key, ha_rows limit,
+ bool need_sort);
+bool select_describe(JOIN *join, bool need_tmp_table, bool need_order,
+ bool distinct);
+bool explain_data_modification(select_result_interceptor *result);
+
+#endif /* SQL_EXPLAIN_INCLUDED */
=== modified file 'sql/opt_range.h'
--- a/sql/opt_range.h 2011-03-22 11:44:40 +0000
+++ b/sql/opt_range.h 2011-04-01 13:53:57 +0000
@@ -1,4 +1,4 @@
-/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@@ -427,8 +427,6 @@ protected:
friend uint quick_range_seq_next(range_seq_t rseq, KEY_MULTI_RANGE *range);
friend range_seq_t quick_range_seq_init(void *init_param,
uint n_ranges, uint flags);
- friend void select_describe(JOIN *join, bool need_tmp_table, bool need_order,
- bool distinct,const char *message);
friend class QUICK_SELECT_DESC;
friend class QUICK_INDEX_MERGE_SELECT;
friend class QUICK_ROR_INTERSECT_SELECT;
=== modified file 'sql/sql_class.h'
--- a/sql/sql_class.h 2011-03-24 08:00:03 +0000
+++ b/sql/sql_class.h 2011-04-01 13:53:57 +0000
@@ -3111,6 +3111,14 @@ public:
*/
virtual void cleanup();
void set_thd(THD *thd_arg) { thd= thd_arg; }
+
+ /*
+ If we execute EXPLAIN SELECT ... LIMIT (or any other EXPLAIN query)
+ we have to ignore LIMIT value sending EXPLAIN output rows since
+ LIMIT value belongs to the underlying query, not to the whole EXPLAIN.
+ */
+ void reset_offset_limit_cnt() { unit->offset_limit_cnt= 0; }
+
#ifdef EMBEDDED_LIBRARY
virtual void begin_dataset() {}
#else
=== modified file 'sql/sql_delete.cc'
--- a/sql/sql_delete.cc 2011-03-17 17:39:31 +0000
+++ b/sql/sql_delete.cc 2011-04-01 13:53:57 +0000
@@ -35,6 +35,7 @@
#include "sp_head.h"
#include "sql_trigger.h"
#include "transaction.h"
+#include "opt_explain.h"
#include "records.h" // init_read_record,
// end_read_record
@@ -60,6 +61,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *
ha_rows deleted= 0;
bool reverse= FALSE;
bool skip_record;
+ bool need_sort= FALSE;
ORDER *order= (ORDER *) ((order_list && order_list->elements) ?
order_list->first : NULL);
uint usable_index= MAX_KEY;
@@ -144,6 +146,15 @@ bool mysql_delete(THD *thd, TABLE_LIST *
/* Update the table->file->stats.records number */
table->file->info(HA_STATUS_VARIABLE | HA_STATUS_NO_LOCK);
ha_rows const maybe_deleted= table->file->stats.records;
+
+ if (thd->lex->describe)
+ {
+ bool err= msg_describe("Using delete_all_rows", maybe_deleted);
+ delete select;
+ free_underlaid_joins(thd, select_lex);
+ DBUG_RETURN(err);
+ }
+
DBUG_PRINT("debug", ("Trying to use delete_all_rows()"));
if (!(error=table->file->ha_delete_all_rows()))
{
@@ -169,14 +180,31 @@ bool mysql_delete(THD *thd, TABLE_LIST *
Item::cond_result result;
conds= remove_eq_conds(thd, conds, &result);
if (result == Item::COND_FALSE) // Impossible where
+ {
limit= 0;
+
+ if (thd->lex->describe)
+ {
+ bool err= msg_describe("Impossible WHERE");
+ delete select;
+ free_underlaid_joins(thd, select_lex);
+ DBUG_RETURN(err);
+ }
+ }
}
#ifdef WITH_PARTITION_STORAGE_ENGINE
if (prune_partitions(thd, table, conds))
- {
+ { // No matching records
+ if (thd->lex->describe)
+ {
+ bool err= msg_describe("No matching records");
+ delete select;
+ free_underlaid_joins(thd, select_lex);
+ DBUG_RETURN(err);
+ }
+
free_underlaid_joins(thd, select_lex);
- // No matching record
my_ok(thd, 0);
DBUG_RETURN(0);
}
@@ -219,23 +247,34 @@ bool mysql_delete(THD *thd, TABLE_LIST *
DBUG_RETURN(TRUE);
}
}
+
+ if (order)
+ {
+ table->update_const_key_parts(conds);
+ order= simple_remove_const(order, conds);
+
+ usable_index= get_index_for_order(order, table, select, limit,
+ &need_sort, &reverse);
+ }
+
+ if (thd->lex->describe)
+ {
+ bool err= table_describe(table, select, usable_index, limit, need_sort);
+ delete select;
+ free_underlaid_joins(thd, select_lex);
+ DBUG_RETURN(err);
+ }
+
if (options & OPTION_QUICK)
(void) table->file->extra(HA_EXTRA_QUICK);
- if (order)
+ if (need_sort)
{
uint length= 0;
SORT_FIELD *sortorder;
ha_rows examined_rows;
ha_rows found_rows;
- table->update_const_key_parts(conds);
- order= simple_remove_const(order, conds);
-
- bool need_sort;
- usable_index= get_index_for_order(order, table, select, limit,
- &need_sort, &reverse);
- if (need_sort)
{
DBUG_ASSERT(usable_index == MAX_KEY);
table->sort.io_cache= (IO_CACHE *) my_malloc(sizeof(IO_CACHE),
@@ -361,6 +400,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *
(void) table->file->extra(HA_EXTRA_NORMAL);
cleanup:
+ DBUG_ASSERT(!thd->lex->describe);
/*
Invalidate the table in the query cache if something changed. This must
be before binlog writing and ha_autocommit_...
=== modified file 'sql/sql_insert.cc'
--- a/sql/sql_insert.cc 2011-02-15 17:14:15 +0000
+++ b/sql/sql_insert.cc 2011-04-01 13:53:57 +0000
@@ -76,6 +76,7 @@
#include "transaction.h"
#include "sql_audit.h"
#include "debug_sync.h"
+#include "opt_explain.h"
#ifndef EMBEDDED_LIBRARY
static bool delayed_get_table(THD *thd, MDL_request *grl_protection_request,
@@ -770,6 +771,19 @@ bool mysql_insert(THD *thd,TABLE_LIST *t
/* Restore the current context. */
ctx_state.restore_state(context, table_list);
+ if (thd->lex->describe)
+ {
+ /*
+ Obviously INSERT without the SELECT is not suitable for EXPLAIN, since we
+ don't plan how read tables.
+ So we simply send "No tables used" and stop execution here.
+ */
+
+ bool err= msg_describe("No tables used");
+ free_underlaid_joins(thd, &thd->lex->select_lex);
+ DBUG_RETURN(err);
+ }
+
/*
Fill in the given fields and dump it to the table file
*/
=== modified file 'sql/sql_parse.cc'
--- a/sql/sql_parse.cc 2011-03-17 17:39:31 +0000
+++ b/sql/sql_parse.cc 2011-04-01 13:53:57 +0000
@@ -96,6 +96,7 @@
#include "set_var.h"
#include "mysql/psi/mysql_statement.h"
#include "sql_bootstrap.h"
+#include "opt_explain.h"
#define FLAGSTR(V,F) ((V)&(F)?#F" ":"")
@@ -825,7 +826,7 @@ out:
This is a helper function to mysql_execute_command.
- @note SQLCOM_MULTI_UPDATE is an exception and delt with elsewhere.
+ @note SQLCOM_UPDATE_MULTI is an exception and delt with elsewhere.
@see mysql_execute_command
@returns Status code
@@ -2910,7 +2911,7 @@ end_with_restore_list:
case SQLCOM_REPLACE_SELECT:
case SQLCOM_INSERT_SELECT:
{
- select_result *sel_result;
+ select_insert *sel_result;
DBUG_ASSERT(first_table == all_tables && first_table != 0);
if ((res= insert_precheck(thd, all_tables)))
break;
@@ -2941,21 +2942,26 @@ end_with_restore_list:
lex->duplicates,
lex->ignore)))
{
- res= handle_select(thd, lex, sel_result, OPTION_SETUP_TABLES_DONE);
- /*
- Invalidate the table in the query cache if something changed
- after unlocking when changes become visible.
- TODO: this is workaround. right way will be move invalidating in
- the unlock procedure.
- */
- if (!res && first_table->lock_type == TL_WRITE_CONCURRENT_INSERT &&
- thd->lock)
+ if (lex->describe)
+ res= explain_data_modification(sel_result);
+ else
{
- /* INSERT ... SELECT should invalidate only the very first table */
- TABLE_LIST *save_table= first_table->next_local;
- first_table->next_local= 0;
- query_cache_invalidate3(thd, first_table, 1);
- first_table->next_local= save_table;
+ res= handle_select(thd, lex, sel_result, OPTION_SETUP_TABLES_DONE);
+ /*
+ Invalidate the table in the query cache if something changed
+ after unlocking when changes become visible.
+ TODO: this is workaround. right way will be move invalidating in
+ the unlock procedure.
+ */
+ if (!res && first_table->lock_type == TL_WRITE_CONCURRENT_INSERT &&
+ thd->lock)
+ {
+ /* INSERT ... SELECT should invalidate only the very first table */
+ TABLE_LIST *save_table= first_table->next_local;
+ first_table->next_local= 0;
+ query_cache_invalidate3(thd, first_table, 1);
+ first_table->next_local= save_table;
+ }
}
delete sel_result;
}
@@ -3019,21 +3025,26 @@ end_with_restore_list:
if (!thd->is_fatal_error &&
(del_result= new multi_delete(aux_tables, lex->table_count)))
{
- res= mysql_select(thd, &select_lex->ref_pointer_array,
- select_lex->get_table_list(),
- select_lex->with_wild,
- select_lex->item_list,
- select_lex->where,
- 0, (ORDER *)NULL, (ORDER *)NULL, (Item *)NULL,
- (ORDER *)NULL,
- (select_lex->options | thd->variables.option_bits |
- SELECT_NO_JOIN_CACHE | SELECT_NO_UNLOCK |
- OPTION_SETUP_TABLES_DONE) & ~OPTION_BUFFER_RESULT,
- del_result, unit, select_lex);
- res|= thd->is_error();
+ if (lex->describe)
+ res= explain_data_modification(del_result);
+ else
+ {
+ res= mysql_select(thd, &select_lex->ref_pointer_array,
+ select_lex->get_table_list(),
+ select_lex->with_wild,
+ select_lex->item_list,
+ select_lex->where,
+ 0, (ORDER *)NULL, (ORDER *)NULL, (Item *)NULL,
+ (ORDER *)NULL,
+ (select_lex->options | thd->variables.option_bits |
+ SELECT_NO_JOIN_CACHE | SELECT_NO_UNLOCK |
+ OPTION_SETUP_TABLES_DONE) & ~OPTION_BUFFER_RESULT,
+ del_result, unit, select_lex);
+ res|= thd->is_error();
+ if (res)
+ del_result->abort_result_set();
+ }
MYSQL_MULTI_DELETE_DONE(res, del_result->num_deleted());
- if (res)
- del_result->abort_result_set();
delete del_result;
}
else
=== modified file 'sql/sql_select.cc'
--- a/sql/sql_select.cc 2011-03-29 07:30:44 +0000
+++ b/sql/sql_select.cc 2011-04-01 13:53:57 +0000
@@ -48,6 +48,7 @@
#include <my_bit.h>
#include <hash.h>
#include <ft_global.h>
+#include "opt_explain.h"
#define PREV_BITS(type,A) ((type) (((type) 1 << (A)) -1))
@@ -250,8 +251,6 @@ static bool setup_sum_funcs(THD *thd, It
static bool prepare_sum_aggregators(Item_sum **func_ptr, bool need_distinct);
static bool init_sum_functions(Item_sum **func, Item_sum **end);
static bool update_sum_func(Item_sum **func);
-void select_describe(JOIN *join, bool need_tmp_table,bool need_order,
- bool distinct, const char *message=NullS);
static Item *remove_additional_cond(Item* conds);
static void add_group_and_distinct_keys(JOIN *join, JOIN_TAB *join_tab);
static bool replace_subcondition(JOIN *join, Item **tree,
@@ -2794,8 +2793,8 @@ JOIN::exec()
if (!tables_list && (tables || !select_lex->with_sum_func))
{ // Only test of functions
if (select_options & SELECT_DESCRIBE)
- select_describe(this, FALSE, FALSE, FALSE,
- (zero_result_cause?zero_result_cause:"No tables used"));
+ msg_describe(this, zero_result_cause ? zero_result_cause
+ : "No tables used");
else
{
if (result->send_result_set_metadata(*columns_list,
@@ -2889,10 +2888,12 @@ JOIN::exec()
keys_in_use_for_query))))
order=0;
having= tmp_having;
- select_describe(this, need_tmp,
- order != 0 && !skip_sort_order,
- select_distinct,
- !tables ? "No tables used" : NullS);
+ if (tables)
+ select_describe(this, need_tmp,
+ order != 0 && !skip_sort_order,
+ select_distinct);
+ else
+ msg_describe(this, "No tables used");
DBUG_VOID_RETURN;
}
@@ -11938,7 +11939,7 @@ return_zero_rows(JOIN *join, select_resu
if (select_options & SELECT_DESCRIBE)
{
- select_describe(join, FALSE, FALSE, FALSE, info);
+ msg_describe(join, info);
DBUG_RETURN(0);
}
@@ -22763,590 +22764,6 @@ void JOIN::clear()
}
}
-/**
- EXPLAIN handling.
-
- Send a description about what how the select will be done to stdout.
-*/
-
-void select_describe(JOIN *join, bool need_tmp_table, bool need_order,
- bool distinct,const char *message)
-{
- List<Item> field_list;
- List<Item> item_list;
- THD *thd=join->thd;
- select_result *result=join->result;
- Item *item_null= new Item_null();
- CHARSET_INFO *cs= system_charset_info;
- int quick_type;
- DBUG_ENTER("select_describe");
- DBUG_PRINT("info", ("Select 0x%lx, type %s, message %s",
- (ulong)join->select_lex, join->select_lex->type,
- message ? message : "NULL"));
- /* Don't log this into the slow query log */
- thd->server_status&= ~(SERVER_QUERY_NO_INDEX_USED | SERVER_QUERY_NO_GOOD_INDEX_USED);
- join->unit->offset_limit_cnt= 0;
-
- /*
- NOTE: the number/types of items pushed into item_list must be in sync with
- EXPLAIN column types as they're "defined" in THD::send_explain_fields()
- */
- if (message)
- {
- item_list.push_back(new Item_int((int32)
- join->select_lex->select_number));
- item_list.push_back(new Item_string(join->select_lex->type,
- strlen(join->select_lex->type), cs));
- for (uint i=0 ; i < 7; i++)
- item_list.push_back(item_null);
- if (join->thd->lex->describe & DESCRIBE_PARTITIONS)
- item_list.push_back(item_null);
- if (join->thd->lex->describe & DESCRIBE_EXTENDED)
- item_list.push_back(item_null);
-
- item_list.push_back(new Item_string(message,strlen(message),cs));
- if (result->send_data(item_list))
- join->error= 1;
- }
- else if (join->select_lex == join->unit->fake_select_lex)
- {
- /*
- here we assume that the query will return at least two rows, so we
- show "filesort" in EXPLAIN. Of course, sometimes we'll be wrong
- and no filesort will be actually done, but executing all selects in
- the UNION to provide precise EXPLAIN information will hardly be
- appreciated :)
- */
- char table_name_buffer[NAME_CHAR_LEN];
- item_list.empty();
- /* id */
- item_list.push_back(new Item_null);
- /* select_type */
- item_list.push_back(new Item_string(join->select_lex->type,
- strlen(join->select_lex->type),
- cs));
- /* table */
- {
- SELECT_LEX *last_select= join->unit->first_select()->last_select();
- // # characters needed to print select_number of last select
- int last_length= (int)log10((double)last_select->select_number)+1;
-
- SELECT_LEX *sl= join->unit->first_select();
- uint len= 6, lastop= 0;
- memcpy(table_name_buffer, STRING_WITH_LEN("<union"));
- /*
- - len + lastop: current position in table_name_buffer
- - 6 + last_length: the number of characters needed to print
- '...,'<last_select->select_number>'>\0'
- */
- for (;
- sl && len + lastop + 6 + last_length < NAME_CHAR_LEN;
- sl= sl->next_select())
- {
- len+= lastop;
- lastop= my_snprintf(table_name_buffer + len, NAME_CHAR_LEN - len,
- "%u,", sl->select_number);
- }
- if (sl || len + lastop >= NAME_CHAR_LEN)
- {
- memcpy(table_name_buffer + len, STRING_WITH_LEN("...,"));
- len+= 4;
- lastop= my_snprintf(table_name_buffer + len, NAME_CHAR_LEN - len,
- "%u,", last_select->select_number);
- }
- len+= lastop;
- table_name_buffer[len - 1]= '>'; // change ',' to '>'
- item_list.push_back(new Item_string(table_name_buffer, len, cs));
- }
- /* partitions */
- if (join->thd->lex->describe & DESCRIBE_PARTITIONS)
- item_list.push_back(item_null);
- /* type */
- item_list.push_back(new Item_string(join_type_str[JT_ALL],
- strlen(join_type_str[JT_ALL]),
- cs));
- /* possible_keys */
- item_list.push_back(item_null);
- /* key*/
- item_list.push_back(item_null);
- /* key_len */
- item_list.push_back(item_null);
- /* ref */
- item_list.push_back(item_null);
- /* in_rows */
- if (join->thd->lex->describe & DESCRIBE_EXTENDED)
- item_list.push_back(item_null);
- /* rows */
- item_list.push_back(item_null);
- /* extra */
- if (join->unit->global_parameters->order_list.first)
- item_list.push_back(new Item_string("Using filesort",
- 14, cs));
- else
- item_list.push_back(new Item_string("", 0, cs));
-
- if (result->send_data(item_list))
- join->error= 1;
- }
- else
- {
- table_map used_tables=0;
- uint last_sjm_table= MAX_TABLES;
- for (uint i=0 ; i < join->tables ; i++)
- {
- JOIN_TAB *tab=join->join_tab+i;
- TABLE *table=tab->table;
- TABLE_LIST *table_list= tab->table->pos_in_table_list;
- char buff[512];
- char buff1[512], buff2[512], buff3[512];
- char keylen_str_buf[64];
- String extra(buff, sizeof(buff),cs);
- char table_name_buffer[NAME_LEN];
- String tmp1(buff1,sizeof(buff1),cs);
- String tmp2(buff2,sizeof(buff2),cs);
- String tmp3(buff3,sizeof(buff3),cs);
- extra.length(0);
- tmp1.length(0);
- tmp2.length(0);
- tmp3.length(0);
-
- quick_type= -1;
- item_list.empty();
- /* id */
- item_list.push_back(new Item_uint((uint32)
- join->select_lex->select_number));
- /* select_type */
- item_list.push_back(new Item_string(join->select_lex->type,
- strlen(join->select_lex->type),
- cs));
- if (tab->type == JT_ALL && tab->select && tab->select->quick)
- {
- quick_type= tab->select->quick->get_type();
- if ((quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_MERGE) ||
- (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT) ||
- (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_UNION))
- tab->type = JT_INDEX_MERGE;
- else
- tab->type = JT_RANGE;
- }
- /* table */
- if (table->derived_select_number)
- {
- /* Derived table name generation */
- int len= my_snprintf(table_name_buffer, sizeof(table_name_buffer)-1,
- "<derived%u>",
- table->derived_select_number);
- item_list.push_back(new Item_string(table_name_buffer, len, cs));
- }
- else
- {
- TABLE_LIST *real_table= table->pos_in_table_list;
- item_list.push_back(new Item_string(real_table->alias,
- strlen(real_table->alias),
- cs));
- }
- /* "partitions" column */
- if (join->thd->lex->describe & DESCRIBE_PARTITIONS)
- {
-#ifdef WITH_PARTITION_STORAGE_ENGINE
- partition_info *part_info;
- if (!table->derived_select_number &&
- (part_info= table->part_info))
- {
- Item_string *item_str= new Item_string(cs);
- make_used_partitions_str(part_info, &item_str->str_value);
- item_list.push_back(item_str);
- }
- else
- item_list.push_back(item_null);
-#else
- /* just produce empty column if partitioning is not compiled in */
- item_list.push_back(item_null);
-#endif
- }
- /* "type" column */
- item_list.push_back(new Item_string(join_type_str[tab->type],
- strlen(join_type_str[tab->type]),
- cs));
- /* Build "possible_keys" value and add it to item_list */
- if (!tab->keys.is_clear_all())
- {
- uint j;
- for (j=0 ; j < table->s->keys ; j++)
- {
- if (tab->keys.is_set(j))
- {
- if (tmp1.length())
- tmp1.append(',');
- tmp1.append(table->key_info[j].name,
- strlen(table->key_info[j].name),
- system_charset_info);
- }
- }
- }
- if (tmp1.length())
- item_list.push_back(new Item_string(tmp1.ptr(),tmp1.length(),cs));
- else
- item_list.push_back(item_null);
-
- /* Build "key", "key_len", and "ref" values and add them to item_list */
- if (tab->ref.key_parts)
- {
- KEY *key_info=table->key_info+ tab->ref.key;
- register uint length;
- item_list.push_back(new Item_string(key_info->name,
- strlen(key_info->name),
- system_charset_info));
- length= longlong2str(tab->ref.key_length, keylen_str_buf, 10) -
- keylen_str_buf;
- item_list.push_back(new Item_string(keylen_str_buf, length,
- system_charset_info));
- for (store_key **ref=tab->ref.key_copy ; *ref ; ref++)
- {
- if (tmp2.length())
- tmp2.append(',');
- tmp2.append((*ref)->name(), strlen((*ref)->name()),
- system_charset_info);
- }
- item_list.push_back(new Item_string(tmp2.ptr(),tmp2.length(),cs));
- }
- else if (tab->type == JT_NEXT)
- {
- KEY *key_info=table->key_info+ tab->index;
- register uint length;
- item_list.push_back(new Item_string(key_info->name,
- strlen(key_info->name),cs));
- length= longlong2str(key_info->key_length, keylen_str_buf, 10) -
- keylen_str_buf;
- item_list.push_back(new Item_string(keylen_str_buf,
- length,
- system_charset_info));
- item_list.push_back(item_null);
- }
- else if (tab->select && tab->select->quick)
- {
- tab->select->quick->add_keys_and_lengths(&tmp2, &tmp3);
- item_list.push_back(new Item_string(tmp2.ptr(),tmp2.length(),cs));
- item_list.push_back(new Item_string(tmp3.ptr(),tmp3.length(),cs));
- item_list.push_back(item_null);
- }
- else
- {
- if (table_list->schema_table &&
- table_list->schema_table->i_s_requested_object & OPTIMIZE_I_S_TABLE)
- {
- const char *tmp_buff;
- int f_idx;
- if (table_list->has_db_lookup_value)
- {
- f_idx= table_list->schema_table->idx_field1;
- tmp_buff= table_list->schema_table->fields_info[f_idx].field_name;
- tmp2.append(tmp_buff, strlen(tmp_buff), cs);
- }
- if (table_list->has_table_lookup_value)
- {
- if (table_list->has_db_lookup_value)
- tmp2.append(',');
- f_idx= table_list->schema_table->idx_field2;
- tmp_buff= table_list->schema_table->fields_info[f_idx].field_name;
- tmp2.append(tmp_buff, strlen(tmp_buff), cs);
- }
- if (tmp2.length())
- item_list.push_back(new Item_string(tmp2.ptr(),tmp2.length(),cs));
- else
- item_list.push_back(item_null);
- }
- else
- item_list.push_back(item_null);
- item_list.push_back(item_null);
- item_list.push_back(item_null);
- }
-
- /* Add "rows" field to item_list. */
- if (table_list->schema_table)
- {
- /* in_rows */
- if (join->thd->lex->describe & DESCRIBE_EXTENDED)
- item_list.push_back(item_null);
- /* rows */
- item_list.push_back(item_null);
- }
- else
- {
- double examined_rows;
- if (tab->select && tab->select->quick)
- examined_rows= rows2double(tab->select->quick->records);
- else if (tab->type == JT_NEXT || tab->type == JT_ALL)
- {
- if (tab->limit)
- examined_rows= rows2double(tab->limit);
- else
- {
- tab->table->file->info(HA_STATUS_VARIABLE);
- examined_rows= rows2double(tab->table->file->stats.records);
- }
- }
- else
- examined_rows= join->best_positions[i].records_read;
-
- item_list.push_back(new Item_int((longlong) (ulonglong) examined_rows,
- MY_INT64_NUM_DECIMAL_DIGITS));
-
- /* Add "filtered" field to item_list. */
- if (join->thd->lex->describe & DESCRIBE_EXTENDED)
- {
- float f= 0.0;
- if (examined_rows)
- f= (float) (100.0 * join->best_positions[i].records_read /
- examined_rows);
- item_list.push_back(new Item_float(f, 2));
- }
- }
-
- /* Build "Extra" field and add it to item_list. */
- my_bool key_read=table->key_read;
- if ((tab->type == JT_NEXT || tab->type == JT_CONST) &&
- table->covering_keys.is_set(tab->index))
- key_read=1;
- if (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT &&
- !((QUICK_ROR_INTERSECT_SELECT*)tab->select->quick)->need_to_fetch_row)
- key_read=1;
-
- if (tab->info)
- item_list.push_back(new Item_string(tab->info,strlen(tab->info),cs));
- else if (tab->packed_info & TAB_INFO_HAVE_VALUE)
- {
- if (tab->packed_info & TAB_INFO_USING_INDEX)
- extra.append(STRING_WITH_LEN("; Using index"));
- if (tab->packed_info & TAB_INFO_USING_WHERE)
- extra.append(STRING_WITH_LEN("; Using where"));
- if (tab->packed_info & TAB_INFO_FULL_SCAN_ON_NULL)
- extra.append(STRING_WITH_LEN("; Full scan on NULL key"));
- /* Skip initial "; "*/
- const char *str= extra.ptr();
- uint32 len= extra.length();
- if (len)
- {
- str += 2;
- len -= 2;
- }
- item_list.push_back(new Item_string(str, len, cs));
- }
- else
- {
- uint keyno= MAX_KEY;
- if (tab->ref.key_parts)
- keyno= tab->ref.key;
- else if (tab->select && tab->select->quick)
- keyno = tab->select->quick->index;
-
- if ((keyno != MAX_KEY && keyno == table->file->pushed_idx_cond_keyno &&
- table->file->pushed_idx_cond) || tab->cache_idx_cond)
- extra.append(STRING_WITH_LEN("; Using index condition"));
-
- if (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_UNION ||
- quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT ||
- quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_MERGE)
- {
- extra.append(STRING_WITH_LEN("; Using "));
- tab->select->quick->add_info_string(&extra);
- }
- if (tab->select)
- {
- if (tab->use_quick == QS_DYNAMIC_RANGE)
- {
- /* 4 bits per 1 hex digit + terminating '\0' */
- char buf[MAX_KEY / 4 + 1];
- extra.append(STRING_WITH_LEN("; Range checked for each "
- "record (index map: 0x"));
- extra.append(tab->keys.print(buf));
- extra.append(')');
- }
- else if (tab->select->cond)
- {
- const Item *pushed_cond= tab->table->file->pushed_cond;
-
- if (thd->optimizer_switch_flag(OPTIMIZER_SWITCH_ENGINE_CONDITION_PUSHDOWN) &&
- pushed_cond)
- {
- extra.append(STRING_WITH_LEN("; Using where with pushed "
- "condition"));
- if (thd->lex->describe & DESCRIBE_EXTENDED)
- {
- extra.append(STRING_WITH_LEN(": "));
- ((Item *)pushed_cond)->print(&extra, QT_ORDINARY);
- }
- }
- else
- extra.append(STRING_WITH_LEN("; Using where"));
- }
- }
- if (table_list->schema_table &&
- table_list->schema_table->i_s_requested_object & OPTIMIZE_I_S_TABLE)
- {
- if (!table_list->table_open_method)
- extra.append(STRING_WITH_LEN("; Skip_open_table"));
- else if (table_list->table_open_method == OPEN_FRM_ONLY)
- extra.append(STRING_WITH_LEN("; Open_frm_only"));
- else
- extra.append(STRING_WITH_LEN("; Open_full_table"));
- if (table_list->has_db_lookup_value &&
- table_list->has_table_lookup_value)
- extra.append(STRING_WITH_LEN("; Scanned 0 databases"));
- else if (table_list->has_db_lookup_value ||
- table_list->has_table_lookup_value)
- extra.append(STRING_WITH_LEN("; Scanned 1 database"));
- else
- extra.append(STRING_WITH_LEN("; Scanned all databases"));
- }
- if (key_read)
- {
- if (quick_type == QUICK_SELECT_I::QS_TYPE_GROUP_MIN_MAX)
- {
- QUICK_GROUP_MIN_MAX_SELECT *qgs=
- (QUICK_GROUP_MIN_MAX_SELECT *) tab->select->quick;
- extra.append(STRING_WITH_LEN("; Using index for group-by"));
- qgs->append_loose_scan_type(&extra);
- }
- else
- extra.append(STRING_WITH_LEN("; Using index"));
- }
- if (table->reginfo.not_exists_optimize)
- extra.append(STRING_WITH_LEN("; Not exists"));
-
- if (quick_type == QUICK_SELECT_I::QS_TYPE_RANGE &&
- !(((QUICK_RANGE_SELECT*)(tab->select->quick))->mrr_flags &
- (HA_MRR_USE_DEFAULT_IMPL | HA_MRR_SORTED)))
- {
- /*
- During normal execution of a query, multi_range_read_init() is
- called to initialize MRR. If HA_MRR_SORTED is set at this point,
- multi_range_read_init() for any native MRR implementation will
- revert to default MRR because they cannot produce sorted output
- currently.
- Calling multi_range_read_init() can potentially be costly, so it
- is not done when executing an EXPLAIN. We therefore make the
- assumption that HA_MRR_SORTED means no MRR. If some MRR native
- implementation will support sorted output in the future, a
- function "bool mrr_supports_sorted()" should be added in the
- handler.
- */
- extra.append(STRING_WITH_LEN("; Using MRR"));
- }
- if (need_tmp_table)
- {
- need_tmp_table=0;
- extra.append(STRING_WITH_LEN("; Using temporary"));
- }
- if (need_order)
- {
- need_order=0;
- extra.append(STRING_WITH_LEN("; Using filesort"));
- }
- if (distinct & test_all_bits(used_tables,thd->used_tables))
- extra.append(STRING_WITH_LEN("; Distinct"));
-
- if (tab->loosescan_match_tab)
- {
- extra.append(STRING_WITH_LEN("; LooseScan"));
- }
-
- if (tab->flush_weedout_table)
- extra.append(STRING_WITH_LEN("; Start temporary"));
- if (tab->check_weed_out_table)
- extra.append(STRING_WITH_LEN("; End temporary"));
- else if (tab->do_firstmatch)
- {
- if (tab->do_firstmatch == join->join_tab - 1)
- extra.append(STRING_WITH_LEN("; FirstMatch"));
- else
- {
- extra.append(STRING_WITH_LEN("; FirstMatch("));
- TABLE *prev_table=tab->do_firstmatch->table;
- if (prev_table->derived_select_number)
- {
- char namebuf[NAME_LEN];
- /* Derived table name generation */
- int len= my_snprintf(namebuf, sizeof(namebuf)-1,
- "<derived%u>",
- prev_table->derived_select_number);
- extra.append(namebuf, len);
- }
- else
- extra.append(prev_table->pos_in_table_list->alias);
- extra.append(STRING_WITH_LEN(")"));
- }
- }
- uint sj_strategy= join->best_positions[i].sj_strategy;
- if (sj_is_materialize_strategy(sj_strategy))
- {
- if (join->best_positions[i].n_sj_tables == 1)
- extra.append(STRING_WITH_LEN("; Materialize"));
- else
- {
- last_sjm_table= i + join->best_positions[i].n_sj_tables - 1;
- extra.append(STRING_WITH_LEN("; Start materialize"));
- }
- if (sj_strategy == SJ_OPT_MATERIALIZE_SCAN)
- extra.append(STRING_WITH_LEN("; Scan"));
- }
- else if (last_sjm_table == i)
- {
- extra.append(STRING_WITH_LEN("; End materialize"));
- }
-
- for (uint part= 0; part < tab->ref.key_parts; part++)
- {
- if (tab->ref.cond_guards[part])
- {
- extra.append(STRING_WITH_LEN("; Full scan on NULL key"));
- break;
- }
- }
-
- if (i > 0 && tab[-1].next_select == sub_select_cache)
- {
- extra.append(STRING_WITH_LEN("; Using join buffer ("));
- if ((tab->use_join_cache & JOIN_CACHE::ALG_BNL))
- extra.append(STRING_WITH_LEN("BNL"));
- else if ((tab->use_join_cache & JOIN_CACHE::ALG_BKA))
- extra.append(STRING_WITH_LEN("BKA"));
- else if ((tab->use_join_cache & JOIN_CACHE::ALG_BKA_UNIQUE))
- extra.append(STRING_WITH_LEN("BKA_UNIQUE"));
- else
- DBUG_ASSERT(0);
- if (tab->use_join_cache & JOIN_CACHE::NON_INCREMENTAL_BUFFER)
- extra.append(STRING_WITH_LEN(", regular buffers)"));
- else
- extra.append(STRING_WITH_LEN(", incremental buffers)"));
- }
-
- /* Skip initial "; "*/
- const char *str= extra.ptr();
- uint32 len= extra.length();
- if (len)
- {
- str += 2;
- len -= 2;
- }
- item_list.push_back(new Item_string(str, len, cs));
- }
- // For next iteration
- used_tables|=table->map;
- if (result->send_data(item_list))
- join->error= 1;
- }
- }
- for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit();
- unit;
- unit= unit->next_unit())
- {
- if (mysql_explain_union(thd, unit, result))
- DBUG_VOID_RETURN;
- }
- DBUG_VOID_RETURN;
-}
-
bool mysql_explain_union(THD *thd, SELECT_LEX_UNIT *unit, select_result *result)
{
=== modified file 'sql/sql_show.cc'
--- a/sql/sql_show.cc 2011-03-28 08:10:39 +0000
+++ b/sql/sql_show.cc 2011-04-01 13:53:57 +0000
@@ -20,7 +20,7 @@
#include "sql_priv.h"
#include "unireg.h"
#include "sql_acl.h" // fill_schema_*_privileges
-#include "sql_select.h" // For select_describe
+#include "sql_select.h"
#include "sql_base.h" // close_tables_for_reopen
#include "sql_show.h"
#include "sql_table.h" // filename_to_tablename,
=== modified file 'sql/sql_update.cc'
--- a/sql/sql_update.cc 2011-02-25 16:41:57 +0000
+++ b/sql/sql_update.cc 2011-04-01 13:53:57 +0000
@@ -1,4 +1,4 @@
-/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@@ -38,6 +38,7 @@
#include "records.h" // init_read_record,
// end_read_record
#include "filesort.h" // filesort
+#include "opt_explain.h"
#include "sql_derived.h" // mysql_derived_prepare,
// mysql_handle_derived,
// mysql_derived_filling
@@ -392,7 +393,14 @@ int mysql_update(THD *thd,
#ifdef WITH_PARTITION_STORAGE_ENGINE
if (prune_partitions(thd, table, conds))
- {
+ { // No matching records
+ if (thd->lex->describe)
+ {
+ bool err= msg_describe("No matching records");
+ free_underlaid_joins(thd, select_lex);
+ DBUG_RETURN(err);
+ }
+
free_underlaid_joins(thd, select_lex);
my_ok(thd); // No matching records
DBUG_RETURN(0);
@@ -419,6 +427,13 @@ int mysql_update(THD *thd,
{
DBUG_RETURN(1); // Error in where
}
+ if (thd->lex->describe)
+ {
+ bool err= msg_describe("Impossible WHERE");
+ delete select;
+ free_underlaid_joins(thd, select_lex);
+ DBUG_RETURN(err);
+ }
my_ok(thd); // No matching records
DBUG_RETURN(0);
}
@@ -450,6 +465,15 @@ int mysql_update(THD *thd,
used_key_is_modified= is_key_used(table, used_index, table->write_set);
}
+ if (thd->lex->describe)
+ {
+ bool err= table_describe(table, select, used_index, limit,
+ order && (need_sort||used_key_is_modified));
+ delete select;
+ free_underlaid_joins(thd, select_lex);
+ DBUG_RETURN(err);
+ }
+
#ifdef WITH_PARTITION_STORAGE_ENGINE
if (used_key_is_modified || order ||
partition_key_modified(table, table->write_set))
@@ -1338,24 +1362,29 @@ bool mysql_multi_update(THD *thd,
(MODE_STRICT_TRANS_TABLES |
MODE_STRICT_ALL_TABLES));
- List<Item> total_list;
+ if (thd->lex->describe)
+ res= explain_data_modification(*result);
+ else
+ {
+ List<Item> total_list;
- res= mysql_select(thd, &select_lex->ref_pointer_array,
- table_list, select_lex->with_wild,
- total_list,
- conds, 0, (ORDER *) NULL, (ORDER *)NULL, (Item *) NULL,
- (ORDER *)NULL,
- options | SELECT_NO_JOIN_CACHE | SELECT_NO_UNLOCK |
- OPTION_SETUP_TABLES_DONE,
- *result, unit, select_lex);
-
- DBUG_PRINT("info",("res: %d report_error: %d", res, (int) thd->is_error()));
- res|= thd->is_error();
- if (unlikely(res))
- {
- /* If we had a another error reported earlier then this will be ignored */
- (*result)->send_error(ER_UNKNOWN_ERROR, ER(ER_UNKNOWN_ERROR));
- (*result)->abort_result_set();
+ res= mysql_select(thd, &select_lex->ref_pointer_array,
+ table_list, select_lex->with_wild,
+ total_list,
+ conds, 0, (ORDER *) NULL, (ORDER *)NULL, (Item *) NULL,
+ (ORDER *)NULL,
+ options | SELECT_NO_JOIN_CACHE | SELECT_NO_UNLOCK |
+ OPTION_SETUP_TABLES_DONE,
+ *result, unit, select_lex);
+
+ DBUG_PRINT("info",("res: %d report_error: %d",res, (int) thd->is_error()));
+ res|= thd->is_error();
+ if (unlikely(res))
+ {
+ /* If we had a another error reported earlier then this will be ignored */
+ (*result)->send_error(ER_UNKNOWN_ERROR, ER(ER_UNKNOWN_ERROR));
+ (*result)->abort_result_set();
+ }
}
thd->abort_on_warning= 0;
DBUG_RETURN(res);
=== modified file 'sql/sql_yacc.yy'
--- a/sql/sql_yacc.yy 2011-03-09 20:54:55 +0000
+++ b/sql/sql_yacc.yy 2011-04-01 13:53:57 +0000
@@ -11376,6 +11376,34 @@ describe:
LEX *lex=Lex;
lex->select_lex.options|= SELECT_DESCRIBE;
}
+ | describe_command opt_extended_describe
+ { Lex->describe|= DESCRIBE_NORMAL; }
+ insert
+ {
+ LEX *lex=Lex;
+ lex->select_lex.options|= SELECT_DESCRIBE;
+ }
+ | describe_command opt_extended_describe
+ { Lex->describe|= DESCRIBE_NORMAL; }
+ replace
+ {
+ LEX *lex=Lex;
+ lex->select_lex.options|= SELECT_DESCRIBE;
+ }
+ | describe_command opt_extended_describe
+ { Lex->describe|= DESCRIBE_NORMAL; }
+ update
+ {
+ LEX *lex=Lex;
+ lex->select_lex.options|= SELECT_DESCRIBE;
+ }
+ | describe_command opt_extended_describe
+ { Lex->describe|= DESCRIBE_NORMAL; }
+ delete
+ {
+ LEX *lex=Lex;
+ lex->select_lex.options|= SELECT_DESCRIBE;
+ }
;
describe_command:
Attachment: [text/bzr-bundle] bzr/gleb.shchepa@oracle.com-20110401135357-zy52d4oplvkki5ya.bundle
